Pair your accounts.

Export articles to Mendeley

Get article recommendations from ACS based on references in your Mendeley library.

Pair your accounts.

Export articles to Mendeley

Get article recommendations from ACS based on references in your Mendeley library.

You’ve supercharged your research process with ACS and Mendeley!

STEP 1:
Click to create an ACS ID

Please note: If you switch to a different device, you may be asked to login again with only your ACS ID.

Please note: If you switch to a different device, you may be asked to login again with only your ACS ID.

Please note: If you switch to a different device, you may be asked to login again with only your ACS ID.

MENDELEY PAIRING EXPIRED
Your Mendeley pairing has expired. Please reconnect
ACS Publications. Most Trusted. Most Cited. Most Read
Nutrient-Controlled Niche Differentiation of Western Lake Erie Cyanobacterial Populations Revealed via Metatranscriptomic Surveys
More

OR SEARCH CITATIONS

My Activity
Publications

Figure 1Loading Img
Download Hi-Res ImageDownload to MS-PowerPointCite This:Environ. Sci. Technol. 2016, 50, 2, 604-615
  • Open Access
Article

Nutrient-Controlled Niche Differentiation of Western Lake Erie Cyanobacterial Populations Revealed via Metatranscriptomic Surveys
Click to copy article linkArticle link copied!

View Author Information
† School of Marine and Atmospheric Sciences, Stony Brook University, Stony Brook, New York 11794, United States
‡ NOAA Great Lakes Environmental Research Laboratory, 4840 S. State Road, Ann Arbor, Michigan 48108, United States
§ Canadian Centre for Inland Waters, Environment Canada, Burlington, Ontario L7R 4A6, Canada
*Phone: (631) 632-5043; fax: (631) 632-5070; e-mail: [email protected]
Open PDFSupporting Information (1)

Environmental Science & Technology

Cite this: Environ. Sci. Technol. 2016, 50, 2, 604–615
Click to copy citationCitation copied!
https://doi.org/10.1021/acs.est.5b03931
Published December 10, 2015

Copyright © 2015 American Chemical Society. This publication is licensed under these Terms of Use.

Request reuse permissions

Abstract

Click to copy section linkSection link copied!
High Resolution Image
Download MS PowerPoint Slide

Although toxic cyanobacterial blooms in western Lake Erie threaten drinking water supplies and are promoted by nutrient loading, the precise nutrient regime that selects specific cyanobacteria populations is poorly understood. Here, we assess shifts in cyanobacterial abundances and global gene-expression patterns in response to natural and manipulated gradients in nitrogen and phosphorus to identify gene pathways that facilitate dominance by different cyanobacteria. Gradients in soluble reactive phosphorus shaped cyanobacterial communities and elicited the largest transcriptomic responses. Under high-P conditions (closest to the mouth of the Maumee River), Anabaena and Planktothrix were the dominant cyanobacterial populations, and experimental P and ammonium enrichment promoted nitrogen fixation gene (nifH) expression in Anabaena. For Microcystis, experimental additions of P up-regulated genes involved in phage defense, genomic rearrangement, and nitrogen acquisition but led to lower abundances. Within offshore, low-P regions of the western basin of Lake Erie, Microcystis up-regulated genes associated with P scavenging (pstSCAB, phoX) and dominated cyanobacterial communities. Experimental additions of ammonium and urea did not alter Microcystis abundances but did up-regulate protease inhibitors (aer and mcn gene sets) and microcystin synthetase genes (mcy), with urea enrichment yielding significant increases in microcystin concentrations. Our findings suggest that management plans that reduce P loads alone may not significantly reduce the risk of cyanobacterial blooms in western Lake Erie but rather may promote a shift among cyanobacterial populations (Microcystis, Anabaena, and Planktothrix) toward a greater dominance by toxic strains of Microcystis.

Copyright © 2015 American Chemical Society

Subjects

what are subjects

Introduction

Click to copy section linkSection link copied!
Lake Erie is the shallowest and most eutrophic of the Laurentian Great Lakes. (1) Since the mid-1990s, cyanobacterial biomass has increased significantly in the western basin of Lake Erie, where extensive blooms of Microcystis are common during late summer and early fall. (2-4) These blooms are hypothesized to be promoted by nutrient delivery from tributaries in western Lake Erie, especially the Maumee River. (3, 5, 6) Intense blooms of toxic cyanobacteria are expected to intensify in Lake Erie, (7) and toxins associated with these blooms have become a threat to drinking water supplies to the region. (8, 9)
Primary producers within freshwater ecosystems are frequently thought to be phosphorus- (P) limited (10, 11) and recent studies of cyanobacteria blooms in Lake Erie have shown their interannual intensity is a function of external P loading. (4, 7) During late summer, however, blooms of cyanobacteria in Lake Erie can become limited by nitrogen (N), an occurrence that may alter the relative abundance of different genera. (12, 13) Enhanced N and P loading can also alter the relative abundance of toxic and nontoxic strains of cyanobacteria, including Microcystis. (14) The biochemical pathways potentially important for facilitating shifts in cyanobacteria taxa during blooms remain poorly understood.
Molecular studies of Microcystis have resolved multiple aspects of this cyanobacterium’s ecology. Genetic studies of Microcystis populations in Lake Erie have documented strain diversity, microcystin dynamics, and genetic connectivity among toxic strains. (2, 15, 16) Metagenomic comparisons between cyanobacterial populations in Lake Erie and other large lakes have revealed functional differences between communities. (17) Transcriptomic analyses of Microcystis cultures have identified biochemical pathways up-regulated under N and P limitation (18) and the relationship between exogenous N-supply and microcystin synthetase, whereby N-deprived Microcystis cells display reduced transcription of microcystin synthetase genes and decreased microcystin content as compared to replete N cells. (18) Transcriptomic studies of Microcystis have also explored the diurnal regulation of gene expression (19) and the role of nutrients in influencing transposase transcription. (20) Few studies have explored the transcriptomic responses of Microcystis in an ecosystem setting, and none have considered how altered nutrient regimes affect its dominance among cyanobacterial populations.
Here we present an in situ evaluation of the transcriptomic responses of Microcystis and other potentially toxic cyanobacteria to natural and manipulated nutrient gradients in western Lake Erie (Figure 1). Cyanobacteria-dominated plankton assemblages in regions close to and away from the primary nutrient source (i.e., the Maumee River) were investigated, and incubation experiments were conducted to evaluate responses to N and P enrichment. Concurrent evaluation of cyanobacterial abundances and differential gene expression via whole-transcriptome sequencing permitted the identification of gene pathways important for facilitating shifting dominance among genera.

Figure 1

Figure 1. Map of stations visited during September (hollow circles) and October (red circles) in the western basin of Lake Erie. Right inset displays the composite of MODIS Cyanobacterial Index image for Sept 24th, 2013 from the NOAA Experimental Lake Erie Harmful Algal Bloom Bulletin (http://www.glerl.noaa.gov/res/Centers/HABS/lake_erie_hab/lake_erie_hab.html). Black represents no cyanobacteria detected. Colored pixels indicate the presence of cyanobacteria.

High Resolution Image
Download MS PowerPoint Slide

Materials and Methods

Click to copy section linkSection link copied!
During August of 2013, MODIS satellite images depicted the development of a large bloom of cyanobacteria in the western basin of Lake Erie, extending from the mouth of the Maumee River to the Bass Islands (http://www.glerl.noaa.gov/res/Centers/HABS/lake_erie_hab/lake_erie_hab.html; Figure S1). This bloom persisted through October. On September 12th of 2013, a mid-day sampling transect was conducted through the bloom aboard the R/V Erie Monitor (The Ohio State University) from the mouth of the Maumee River to the Lake Erie Islands that separate the western and central basins of the lake (Figure 1). The stations visited during each transect represented a nutrient gradient in which both N and P typically decline with distance from the mouth of the Maumee River (high-N and -P region). At each station (n = 6), subsurface samples (∼0.25 m) were collected to assess phytoplankton abundance and diversity using a fluoroprobe (BBE Moldenke) to differentiate cyanobacteria from other phytoplankton groups on the basis of photosynthetic accessory pigments. (21) Dissolved (filtered through a combusted EMD Millipore APFB glass-fiber filter) and total nutrient samples were collected, together with water for analysis of photosynthetic efficiency (Fv/Fm), total microcystins, alkaline phosphatase activity (APA), and plankton community composition (preserved with Lugol’s iodine solution; see Sample Analyses section below). At a station with elevated cyanobacterial biomass (as indicated via the Fluoroprobe), 1 L of water was filtered on 20 μm polycarbonate filters for transcriptomic analysis of colonial cyanobacteria, immediately immersed in liquid N, and stored at −80 °C. An additional 60 L of water was collected for a nutrient amendment experiment.
On October 8th of 2013, as part of the Lake Erie harmful algal bloom monitoring program conducted by Environment Canada aboard the Canadian Coast Guard ship Limnos, seven stations were sampled at mid-day across the western basin of Lake Erie (Figure 1). At each station, samples were collected for the analysis of dissolved and total nutrients (see above), total microcystins, and plankton communities (see the Sample Analyses section below). Furthermore, at each site, ∼1 L of surface water was filtered through replicate Millipore 0.22 μm Sterivex filters for transcriptomic analysis; filters were sealed, immediately immersed in liquid N, and stored at −80 °C. Although these filters had a smaller pore size than our experimental samples (see below), our information analyses of transcriptome samples specifically targeted three populations of colonial cyanobacteria (>20 μm): Microcystis, Planktothrix, and Anabaena. Further, transcriptomes collected on different filter types were not compared to each other but rather to other transcriptomes collected at the same time using the same filter type.

Effect of Nutrients on Cyanobacteria

To further assess how nutrients affect the growth and physiology of algal communities in Lake Erie, we filled duplicate 1.1 L bottles (n = 8 for each experimental set) with water collected at station L16 (see above) and were left unamended to serve as a control or amended with nitrogen (2.5 μM urea (5 μM N) or 5 μM ammonium) or inorganic phosphorus (0.3 μM K2HPO4) at the start of the experiment and again after 24 h. Concentrations were chosen to be slightly above background during summer in the western basin of Lake Erie (<2-fold above ambient; Table 1), (13) while the daily delivery was representative of nutrient pulses that can emanate from point sources in the region such as the Maumee River. (3) Bottles were placed in a wire submersible rack at 0.25 m in Fishery Bay near the Franz Theodore Stone Laboratory (The Ohio State University) to provide ambient temperature and light incubation conditions. After 48 h, at mid-day, bottles were processed for the analysis of in vivo chlorophyll a, the phytoplankton abundance was measured with a fluoroprobe, and bulk APA, Fv/Fm, and dissolved and total nutrients (see Sample Analyses section below) were measured. Samples for total microcystin analysis were collected and frozen at −20 °C (see Sample Analyses section below). The remaining volume was then filtered onto 20 μm polycarbonate filters and immediately flash-frozen in liquid N for the transcriptomic analysis of colonial cyanobacteria.
Table 1. Number of Differentially Expressed Genes in Each Category Up-Regulated (↑) and Down-Regulated (↓) for Planktothrix aghardhii NIVA-CYA 15 and Anabaena sp. PCC7108 Relative to the Reference Station (LET7) for LET6 through LET1 or the Control (for +P, +NH4, and +Urea).a
Planktothrix aghardhii NIVA-CYA 15       
categoryLET6LET5LET4LET3LET2LET1+P+NH4+urea
long-chain fatty acid CoA ligase1↑7↑7↑, 9↓7↑, 9↓8↑, 6↓7↑, 8↓1↓  
hypothetical protein3↑, 7↓21↑18↑, 875↓18↑, 1083↓20↑, 470↓18↑, 798↓1↑  
photosynthesis15↓3↑, 2↓55↓55↓1↑, 49↓1↑, 53↓3↓2↑ 
alkaline phosphatase1↓ 15↓16↓11↓15↓1↓  
transporters1↑3↑3↑, 83↓3↑, 101↓3↑, 43↓3↑, 77↓   
mobile elements1↑4↑3↑, 19↓3↑, 24↓2↑, 13↓3↑, 17↓   
cell division  20↓20↓13↓19↓   
Anabaena sp. PCC7108       
categoryLET6LET5LET4LET3LET2LET1+P+NH4+urea
nitrogenase 2↑1↑ 4↑5↑2↑2↑1↓
photosystem II 3↑5↑4↑, 2↓4↑, 1↓2↑, 1↓   
phycobilisome3↓3↓4↓5↓6↓7↓   
transposase 1↑1↑2↑2↑1↑   
a

Functions were binned on the basis of keyword searches in the PATRIC database.

Sample Analyses

Nitrate was analyzed by reducing the nitrate to nitrite using spongy cadmium as per Jones. (22) Ammonium and phosphate were analyzed using techniques from Parsons et al. (23) Total dissolved N and P were analyzed using persulfate digestion techniques from Valderrama. (24) These nutrient analyses provided 100 ± 10% recovery of standard reference material (SPEX CertiPrep) for nitrate, ammonium, phosphate, total dissolved N, and total dissolved P. Maximum quantum efficiency of photosystem II (PSII) was estimated from in vivo (Fi) and DCMU (3,4-dichlorophenyl-1,1-dimethylurea)-enhanced in vivo fluorescence (Fm) of each sample measured on a Turner Designs TD-700 fluorometer (EM filter of >665 nm and EX filter of 340–500 nm). All readings were blank-corrected using 0.2 μm of filtered lake water. DCMU blocks electron transfer between PSII and PSI and yields maximal fluorescence, and previous studies have demonstrated that Fv/Fm can be diagnostic of nutrient limitation. (25, 26) Bulk APA was measured on a Turner Designs TD-700 fluorometer (EM filter of 410–600 nm and EX filter of 300–400 nm) using 4-methylumbelliferone phosphate (250 mM concentration) as the substrate. (27) APA measured by this assay has been shown to be significantly correlated with the expression of the gene-encoding alkaline phosphatase (phoX) in cultures of Microcystis aeruginosa clone LE-3. (28)
Whole water samples were analyzed for total microcystins by freezing samples at −20 °C for >24 h and then lysing cells using an Abraxis QuikLyse Cell Lysis kit. Microcystin concentrations within lysed samples were quantified on a SpectraMax Plus 384 plate-reading spectrophotometer using the Abraxis microcystins/nodularins (ADDA) ELISA colorimetric immunoassay according to the manufacturer’s instructions. This assay is congener-independent, being sensitive to the ADDA moiety (29) that is found in almost all microcystins, and provided an analytical precision of ±2% and a 96 ± 2% recovery of spiked samples.
For samples collected in September, Microcystis biomass was measured with an inverted microscope equipped with a Nikon DS-Vi1 camera using Lugol’s preserved samples. An entire gridded Sedgewick–Rafter chamber (1 mL) was visually scanned, and Microcystis colonies, as well as Planktothrix and Anabaena colonies, were quantified and measured using NIS-Elements imaging software (version 3.22.11). The area of each Microcystis colony was converted to cells per milliliter according to Watzin et al. (30) For samples collected in October, samples were enumerated with the Utermöhl technique for algal biomass and taxonomic composition. (31) Depending on sample density, subsamples of 2–5 mL were settled for 24 h and counted at 100× or 400× using a Leica DM inverted-phase microscope, enumerating a minimum of 100 settled units for the most abundant taxa. Cell counts were converted to biomass from average measured cell volumes, and taxa were identified to genus or species levels according to major taxonomic sources. Colonial and filamentous forms were measured individually and biomass calculated as a function of average cell density per average biovolume. Although cyanobacterial quantification methods differed, the September and October samples sets were not compared to each other but rather to other samples collected at the same time and thus quantified in the same manner.

RNA Isolation and Sequencing

RNA was extracted from duplicate biological replicate samples using the RNeasy Mini Kit with RNAprotect bacteria reagent (Qiagen) as outlined by Ilikchyan et al. (32) Briefly, a polycarbonate filter containing filtered cells was transferred to a 15 mL Falcon tube, and 2 mL of TE buffer was added to wash cells from the filter. Then, 4 mL of RNAprotect bacteria reagent was added, and the mixture was allowed to incubate for 5 min at room temperature. Following centrifugation for 10 min at 2000g, the supernatant was transferred out of the tube, and 200 μL of TE buffer with lysozyme (Sigma) and proteinase K (Qiagen) was added. The pellet was resuspended by pipetting and transferred to a 1.5 mL microcentrifuge tube and allowed to incubate for 10 min at room temperature. The remainder of the RNeasy Mini Kit protocol was then followed according to the manufacturer’s instructions. Extraction of RNA from Sterivex filters followed Ilikchyan et al., (32) with an added 5 min incubation before passing RNAprotect through the filter and the RNA lysis buffer incubation being reduced to 30 min. For both polycarbonate filter and Sterivex filter samples, on-column DNase digestion was performed on RNA samples using RNase-free DNase (Qiagen) according to the manufacturer’s instructions. Ribosomal RNA was removed from total RNA (∼3 μg) using an Epicenter Ribo-Zero magnetic kit (bacteria) and Ribo-Zero magnetic kit (plant leaf) according to the manufacturer’s instructions. Both kits were combined by mixing the Ribo-Zero rRNA Removal Solutions at a 50:50 concentration per manufacturer recommendation. After rRNA depletion, samples were purified using a Qiagen RNeasy MinElute cleanup kit according to the instructions outlined by the Epicenter Ribo-Zero magnetic kit. Post-digested RNA was assessed for quantity with a Qubit 2.0 fluorometer and quality with an Agilent Bioanalyzer. Samples were stored at −80 °C until sequencing. Sequencing libraries were prepared using a TruSeq RNA Sample Preparation Kit v2 (Illumina) according to the manufacturer’s instructions, skipping the poly-A pull-down step. Library prep and sequencing of 100 bp single-end reads per library was performed by the JP Sulzberger Columbia Genome Center (New York, NY) on an Illumina HiSeq 2000 system.

Read Mapping and Analysis

Raw reads were initially characterized with FastQC (http://www.bioinformatics.Babraham.ac.uk/projects/fastqc/). Trimming ambiguous reads slightly improved alignment rates (+∼1%) but decreased the number of unique alignments. As such, ambiguous or low-quality reads were not trimmed prior to read mapping. Reads were mapped to the M. aeruginosa NIES-843 genome (33) using RSEM v1.2.11 (34) with Bowtie 2 (35) and parameters recommend by the RSEM authors. We used Bowtie 2 because it is generally faster than Bowtie 1, supports reads longer than 50 bp, and provides alignments based on a quantitative scoring scheme rather than mismatch rate. (35) Differential expression between treatments and the reference condition was computed with EBseq (36) within RSEM using the soft-threshold option and median normalization. EBseq uses an empirical Bayesian method that has increased power of detection over most count-based methods, and true positive rates are generally independent of sample size and outliers. (36, 37) Genes with zero-read counts across all comparisons were not considered in differential expression analysis. In addition, because rRNA removal methods do not completely remove all rRNA, transcripts mapping to 5S, 16S, or 23S rRNA genes were removed prior to differential expression analysis. Comparisons were accepted as significant, with the false discovery rate (FDR) controlled at 0.05 (in EBseq PPDE ≥ 0.95). For the field samples, differential expression was calculated by comparing the station closest to the mouth of the Maumee River (LET7) to other stations (LET1–6). For the bottle incubation experiments, all treatments were compared to the control treatment. When there were only a small number of genes responding in bottle incubation experiments, an additional comparison to the initial as the reference condition was performed. Taxonomic profiling of each sequenced sample was conducted with MetaPhlAn v1.7.7 (38) that maps raw sequence reads to a database of predefined clade-specific microbial marker genes. MetaPhlAn identified to the order level two more abundant cyanobacteria: Oscillatoriales and Nostocales. Microscopy allowed us to assign a genus to these orders, and as such, we mapped to two genomes representing significant fractions of the microbial community, as identified by these two methods (Planktothrix and Anabaena). Of the Anabaena genomes examined (Anabaena sp. 90, Anabaena variabilis ATCC 29413, and Anabaena sp. PCC 7108), Anabaena sp. PCC7108 had the largest overall alignment rates (0.02–0.57; Table S4). Similarly, among the Planktothrix genomes examined (Planktothrix agardhii NIVA-CYA 563 and NIVA-CYA 15), Planktothrix agardhii NIVA-CYA 15 had the largest fraction of mapped transcripts (0.06–2.74%; Table S5) and was chosen to elicit genetic responses of this group.
Differentially expressed genes for Microcystis were assigned functional categories on the basis of categories found in CyanoBase for the Microcystis NIES-843 genome (http://genome.microbedb.jp/cyanobase/Microcystis). The blastp suite (http://blast.ncbi.nlm.nih.gov) was used to elucidate putative functions of hypothetical genes using an E-value cutoff of 1 × 10–5. The Phyre2 server was used to predict function on the basis of protein structure for some genes. (39) The PATRIC Web site (http://patricbrc.org/portal/portal/patric/Home) was used to identify genes and annotations for the Planktothrix and Anabaena genomes. (40) The Illumina sequences reported in this paper have been deposited in the National Center for Biotechnology Information’s Sequence Read Archive (accession no. SRP047492). One-way analysis of variance (ANOVA) and regression analyses of parameters measured during experiments or across transects were performed using SigmaPlot version 11.0 (build 11.1.0.102). Post-hoc multiple comparisons were performed with Tukey tests.

Results

Click to copy section linkSection link copied!

Lake Properties

Abundance of Microcystis was low at the mouth of the Maumee River but increased within the western basin of Lake Erie, while both alkaline phosphatase activity (APA) and photosynthetic efficiency (Fv/Fm) increased with distance from the mouth of the Maumee River (Table S1). Dissolved nutrient concentrations (nitrate, ammonium, and phosphate) were highest near the Maumee River and lower east of this region (Table S2). Microcystin levels were generally higher and more variable in September (3.8 ± 3.2 μg L–1) compared to levels in October (0.96 ± 0.27 μg L–1; Table S1).

Transcriptomic Sequencing

Transcriptomic sequencing yielded, on average, 31 million 100 bp reads per sample (Table S3). Taxonomic profiling of transcripts with MetaPhlAn indicated that the microbial community was largely dominated by Microcystis (>70%) in the open waters of western Lake Erie (stations LET5 to LET1), whereas regions closer to the Maumee River were dominated by Anabaena (>70%; Figure 2A). A total of 20% of transcripts aligned to the reference Microcystis genome (Table S3), with the exception of three October samples that displayed lower alignment rates (2% on average; Table S3). Of the putative protein-encoding genes in the Microcystis genome (6312), between 3% and 20% displayed significant differential expression (Figure S2). Planktothrix and Anabaena displayed lower alignment rates (up to 13% and 1%, respectively; Table S4, S5). MetaPhlAn also identified a Flavobacterium representing a low percentage of expressed transcripts (<4%) at all stations but LET3 (>13%), with other individual prokaryotes representing <9% of all transcripts (Figure 2A).

Figure 2

Figure 2. (A) Prokaryotic community analysis via MetaPhlAn displaying the average percent transcripts during the October transect across the western basin of Lake Erie. (B) SRP concentrations at each station (station LET4 was below detection limits (0.003 μM) and (C) the log2 fold change in gene expression of genes involved in phosphate transport in Microcystis relative to station LET7. Error bars represent the standard deviation between biological replicates (n = 2). Stations are ordered from west to east as appearing in Figure 1.

High Resolution Image
Download MS PowerPoint Slide

Transcriptomic Responses across Western Lake Erie

Microcystis

The number of significant, differentially expressed Microcystis genes increased with distance from the reference location (LET7) moving east along the cruise track (Figure S2A). Populations within midtransect (LET3) displayed the largest number of significant differentially expressed genes (445) with stations farther to the east having a slightly lower number (Figure S2A). Several genes involved in N transport and metabolism displayed significant increases in expression relative to the Maumee River station (LET7). For example, at station LET5 genes encoding a nitrate–nitrite transport permease protein (nrtB), ferredoxin–nitrite reductase (nirA), and ammonium permease (amt1) displayed large increases in expression (>2 log2 fold change; Figure S3). In contrast, only one gene related to N metabolism, encoding glutamate dehydrogenase (gdhA), displayed lower transcript abundance at all stations compared to the reference site (Figure S3).
Microcystis genes related to the transport and metabolism of P displayed strong gradients in expression across Lake Erie. A gene encoding a periplasmic phosphate-binding protein (pstS, MAE18310) had large increases in transcript abundance relative to LET7 at all stations but LET6 (the closest station to LET7), with log2 fold changes ranging from 3.36 to 6.87 and being inversely correlated with levels of SRP (p < 0.01; Figure 2B,C; Figure S4). At the only station with levels of SRP below detection limits (<0.1 μM; station LET4; Figure 2B), a number of additional phosphate transport genes displayed increased transcript abundance, including one phosphate permease (pstA) and three phosphate-binding proteins (pstB, pstB2, and sphX) with log2 fold change values ranging from 1.84 to 6.87 (Figure 2C, Figure S4).
Expression of genes involved in the production of microcystin and other secondary metabolites also changed across the western basin of Lake Erie. At all stations, genes responsible for the production of the protease inhibitors, aeruginosin (aer gene set) and cyanopeptolin (mcn gene set) (42) displayed large decreases in transcript abundance moving away from the mouth of the Maumee River (Figure 3). Several microcystin synthetase genes were differentially expressed; mycD and mcyG displayed decreased transcript abundance at station LET2, while mcyA and mcyD had increased transcript abundance at LET3 (Figure 3). A large number of genes encoding transposases (genes involved in mediating the rearrangement of transposable elements within the genome) were differentially expressed at all stations, with the largest number observed in the middle part of the western basin at station LET3 (70; Figures 4A and S5). A similar pattern was observed with the expression of genes putatively involved in phage defense (43) with the highest number of differentially expressed genes being observed at stations LET4 and LET3 (Figure 4B).

Figure 3

Figure 3. Heat maps of secondary metabolite genes (microcystin (mcy), aeruginosin (aer), and cyanopeptolin (mcn)) expression (log2 fold change) for Microcystis and DIN concentration (μM) for each station and experimental treatment. White boxes indicate genes not displaying significant differential expression at each station relative to LET7 and under each treatment relative to the control. Blue colors correspond to a significant decrease in transcript abundance, while red colors correspond to a significant increase in transcript abundance. Stations are ordered from west to east as appearing in Figure 1. Nutrient additions experiments were conducted with water collected at station L16.

High Resolution Image
Download MS PowerPoint Slide

Figure 4

Figure 4. (A) The number of significant differentially expressed transposase genes in each transposase family and (B) the number of significant differentially expressed genes potentially involved in phage defense per station for Microcystis relative to station LET7. Blue denotes an increase in transcript abundance, and yellow denotes a decrease in transcript abundance. Stations are ordered from west to east as appearing in Figure 1.

High Resolution Image
Download MS PowerPoint Slide

Planktothrix

Planktothrix decreased in abundance moving east from the Maumee River (Figure S6) and displayed a significant down-regulation of genes related to photosynthesis, cell division, and hypothetical proteins at stations farthest from the Maumee (stations LET1–4; Table 1, Figure S7A). Of the genes with increased transcript abundance (numbering <50), many were annotated as long-chain fatty-acid CoA ligases, which may be involved in lipid recycling (Table 1). (44) There were also multiple mobile elements, three transporters, and numerous hypothetical proteins with increased transcript abundance at all stations (Table 1).

Anabaena

Although the abundance of Anabaena decreased moving east from the Maumee River (Figure S6), its number of significant differentially expressed genes increased (Figure S8A). Numerous genes encoding nitrogenase (nifH) were up-regulated in stations farthest from the reference station (LET2 and LET1) as were several transposases (LET1–5; Table 1). Anabaena displayed a mixed response with regards to photosynthesis genes, with phycobilisomes being down-regulated and photosystem II genes being up-regulated (Table 1).

Nutrient Amendment Experiments

Relative to the unamended control, Microcystis abundances significantly decreased in response to P enrichment (p < 0.001) but did not change in response to urea or ammonium (Figure 5A). In contrast, total cyanobacterial biomass displayed significant increases in response to ammonium, urea, and P (p < 0.05; Figure 5D) relative to the control. Bulk APA was significantly higher in treatments amended with N relative to the P treatment, averaging 0.29 ± 0.01 (nmol mL–1 h–1) (p < 0.001; Figure 5B). Urea enrichment yielded a significant increase in microcystin concentrations (from 3.87 ± 0.40 to 10.90 ± 0.49 (μg L–1 MC-LR equivalents)) relative to the control and initial conditions (p < 0.001; Figure 5C). Nitrate, urea, and SRP were at submicromolar concentrations in all treatments by the end of the experiment (Table S6), whereas ammonium levels were highest in the + P treatment (1.66 ± 0.18 μM) and lower but similar in all other treatments (∼1 μM, Table S6).

Figure 5

Figure 5. (A) Microcystis cell densities, (B) bulk alkaline phosphatase activity, (C) microcystin concentrations, and (D) cyanobacterial abundances as measured with a Fluoroprobe at the time of harvest for the nutrient amendment experiments. Error bars represent the standard deviation between biological replicates (n = 2). Star indicates significant difference relative to the control treatment (A, C, and D) or +P treatment (B) (p < 0.001). Microcystins were measured as MC–LR equivalents.

High Resolution Image
Download MS PowerPoint Slide

Transcriptomic Responses to Nutrient Amendments

Microcystis

The largest transcriptional response in Microcystis was observed in the P amendment treatment, with more than 1300 genes differentially expressed relative to the control. In contrast, treatments amended with ammonium or urea, the transcriptional response of Microcystis was smaller (579 and 524 genes, respectively; Figure S2B). Among identified genes, many were involved in photosynthesis, respiration, and translational functions (Table S7). Regarding N metabolism, P additions increased transcription of genes encoding a nitrate and nitrite reductase as well as genes within the nitrate–nitrite transport system (nrtABCD; Figure S3) but decrease transcription of glutamate synthase (gln A, gln B, gltB, gltD) genes (Figure S3). Urea additions increased the abundance of transcripts for genes encoding cyanase, an enzyme involved in the degradation of cyanate, a product of urea degradation (MAE10370; cynS), and evidencing active use of this compound by Microcystis. Urea additions also up-regulated nitrate and nitrite reductases (MAE53960, narB and MAE18410, nirA; Figure S3). Additions of ammonium enhanced transcription of a gene encoding glutamate–ammonia ligase (MAE19270, gln A; Figure S3) that is involved in the production of l-glutamine from ammonia. A gene encoding cyanophycinase (MAE29150, cphB), which degrades cyanophycin (a N-rich reserve material) (45) decreased in transcript abundance in the urea and ammonium treatments, while a second gene annotated as cphB (MAE27450) decreased in transcript abundance when P was added. The cyanophycin synthetase gene (MAE27460, cphA) displayed lowered transcript abundance in all treatments (Figure S3).
Phosphorus transport and metabolism genes were highly responsive to N and P enrichment. When P was added, many phosphate transport genes within the pstSCAB gene set and a phosphate transport system regulatory protein (MAE52660, phoU) decreased in transcript abundance (Figure 6A, Figure S4). When nitrogen (urea or ammonium) was added, these genes displayed significant increases in transcript abundance (Figure 6A, Figure S4). In addition, the gene encoding alkaline phosphatase (MAE30190, phoX) increased in transcript abundance when ammonium was added, as did a gene involved in the synthesis of polyphosphate (MAE01300, ppk1; Figure 6A, Figure S4).

Figure 6

Figure 6. (A) The log2 fold change in gene expression relative to the control of genes involved in phosphate transport and metabolism for Microcystis, (B) the number of significant differentially expressed transposase genes in each transposase family for the nutrient amendment experiments, and (C) the number of significant differentially expressed genes potentially involved in phage defense relative to the control for Microcystis.

High Resolution Image
Download MS PowerPoint Slide
The expression of transposase genes in Microcystis was sensitive to nutrient amendments. In response to P enrichment, 141 transposases were differentially expressed, with 89 increasing in transcript abundance, whereas there was a smaller response to N (urea or ammonium; <50 genes, >50% increasing in transcript abundance; Figure 6B, Figure S9). A parallel response was observed among phage defense genes, whereby P enrichment promoted an order of magnitude larger differential response than N (Figure 6C). P enrichment also promoted the largest response in genes involved in DNA replication, restriction, modification, recombination, and repair with 12 genes in this functional category being up-regulated (Figure S10). The addition of ammonium increased transcript abundance of three genes within the mcy cassette (mcyB, mcyD, and mcyG), while the addition of urea increased the transcript abundance of the mcyB gene only (Figure 3). The expression of other secondary metabolites responded similarly, with two genes involved in aeruginosin and cyanopeptolin synthetase (protease inhibitors that may be involved in grazer defense; aerA and mcnG, respectively) displaying increases in transcript abundance when ammonium was added and with urea additions eliciting the up-regulation of mcnF (Figure 3).

Planktothrix

It was found that Planktothrix became less abundant during the experiment, declining from 4% to <3% of expressed transcripts (Figure S11). Relative to the initial or control, P enrichment produced the largest number of differentially expressed genes (6 and 27, respectively; Figure S7B, C) with the majority of these down-regulated. No genes were differentially expressed with urea enrichment relative to the control, although a similar number of genes to P enrichment were differentially expressed relative to the initial condition (Figure S7B, C). As in the field transect, many of the up-regulated genes were involved in fatty-acid metabolism, whereas the down-regulated genes were involved in photosynthesis, regardless of treatment (Table 1). In a response similar to that of Microcystis, P enrichment elicited a decrease in Planktothrix alkaline phosphatase transcripts (Table 1).

Anabaena

Anabaena became less abundant during the experiment, declining from 14% to <4% of expressed transcripts (Figure S11). Relative to the control, enrichment with ammonium produced the largest number of differentially expressed genes, whereas urea produced the smallest number (Figure S8B). Relative to the initial condition, a similar number of genes were differentially expressed regardless of treatment (∼62; Figure S8C). When compared to the control, genes encoding nitrogenase (nifH) increased in transcript abundance when P or ammonium were added (Table 1). Enrichment with ammonium also increased transcript abundance of a putative transposase by ∼2-fold (Table 1).

Discussion

Click to copy section linkSection link copied!
This study concurrently evaluated the abundances and transcriptomes of cyanobacteria as a function of nutrient gradients across western Lake Erie, providing novel insight regarding key physiological pathways that shape the niche of populations within this system. Changing SRP concentrations elicited the largest transcriptomic response among cyanobacteria. In Microcystis, expression of P-scavenging genes was heightened in the presence of low-P and decreased with higher P (Figures 2C, 4, and 5A). Furthermore, the station with the lowest SRP levels in Lake Erie (LET4, Figure 2B) displayed the largest up-regulation of five of these P scavenging genes (pstSCAB; Figure 2C). The degree of up-regulation (1.84–6.87 log2 fold change) of these genes was similar to that observed in P-limited cultures of Microcystis (0.83–5.63 log2 fold change), (18) suggesting that within Lake Erie, Microcystis populations recruit these proteins to adapt to P limitation and persist within the lake despite very low levels of SRP. Unlike Microcystis, Planktothrix down-regulated its alkaline phosphatase genes in response to decreased SRP, and no P-scavenging genes were differentially expressed in Anabaena populations (Table 1).
Nitrogen had a smaller but broad effect on transcript abundance in Microcystis. Urea enrichment did not alter expression of genes encoding urea transporters (urtABCDE) or genes encoding the enzyme urease (ureABCDEFG), demonstrating these populations were not N-limited given the strong response of these genes to N limitation in culture. (18, 41) However, it is possible urease is constitutively expressed in Microcystis, as has been reported for other microbes, (42, 43) or the added urea was quickly metabolized and the expression of urease had already ceased when cells were harvested. A gene encoding cyanase (MAE10370, cynS) displayed elevated transcript abundance during urea enrichment (Figure S3). Cyanate can be produced from the decomposition of urea, and because it is toxic at high levels, some cyanobacteria express a cyanase to detoxify this compound. (44, 45) Therefore, cynS expression may serve as a marker for use of urea by Microcystis populations.
Some microcystin synthetase genes were up-regulated when exposed to higher ammonium and urea levels, and there was a significant increase in microcystin concentrations when natural populations of cyanobacteria were provided urea (Figure 5C). Intracellular levels of microcystin, a N-rich compound in Microcystis, generally increase under high concentrations of bioavailable N (ammonium or urea), (18, 46-48) and urea has been shown to increase microcystin concentrations in freshwater systems. (49, 50) Beyond microcystin, the synthesis of other secondary metabolites in Microcystis seems to be promoted by high N levels. The genes responsible for the production of the protease inhibitors, aeruginosin (aer gene set) and cyanopeptolin (mcn gene set), two N-rich compounds, displayed significant decreases in transcript abundance moving away from the high nitrogen levels near the mouth of the Maumee River and significant increases in gene expression when nitrogen levels were experimentally enhanced. Therefore, nitrogen loading may promote Microcystis blooms both directly via the enhancement of growth (14) as well as indirectly via the synthesis of protease inhibitors that discourage zooplankton grazing (51, 52) and thus facilitate bloom proliferation. (53, 54)
In the presence of high concentrations of nutrients, microbes often synthesize storage products that can serve as reserve material during nutrient stress. (55) A pair of such storage products in cyanobacteria, cyanophycin (for N) and polyphosphate (for P), are formed through cyanophycin synthetase and polyphosphate (polyP) kinase, respectively. (56, 57) Additions of N elicited a decrease in transcript abundance of the genes involved in the breakdown (MAE29150, cphB) and synthesis (MAE27460, cphA) of cyanophycin. This response was partly unexpected because additions of N have been shown to stimulate synthesis of cyanophycin in some cyanobacteria, including Aphanocapsa (58) and Planktothrix. (59) However, N additions in these previous studies were more than 1000-fold higher than the environmentally relevant N additions used in this study, which were seemingly large enough to slow the use of cyanophycin (lower cphB expression) but not high enough to induce cyanophycin synthesis (cphA). Regarding polyP, the addition of ammonium significantly increased transcripts of polyphosphate kinase (MAE01300, ppk1), whereas P additions had the opposite effect. This response, although seemingly counterintuitive, is consistent with studies of other phytoplankton (60, 61) and cultured Microcystis, (18) where under P stress there is an increase in polyphosphate production, and the addition of P causes a decrease in polyP levels. (57) Under low-P conditions, therefore, Microcystis up-regulates P transporters (e.g., pstS) that shunt orthophosphate to polyP that is likely utilized only under periods of extreme P stress. (57) Such a mechanism for carefully titering polyP levels likely facilitates the persistence of Microcystis blooms within low- (but dynamic) P environments such as western Lake Erie.
Transposases are thought to be the most abundant genes in nature, (62) are involved in mediating the movement of transposable elements within a genome, and can enhance a cell’s ability to adapt to changing environmental conditions. (63)Microcystis contains more transposable elements than other cyanobacteria, comprising >10% of the genome in some strains of this genus, (64) providing a high degree of genome plasticity, (33, 65) and potentially contributing toward its dominance in freshwater systems. (64) In this study, during P enrichment, 141 genes encoding transposases were differentially expressed, with 89 displaying increases in transcript abundance (Figures 6B and S9). P enrichment also induced the up-regulation of the largest number of genes involved in DNA repair (Figure S10), further suggesting active genome rearrangement and repair under high-P conditions. When N was added (urea or ammonium), a smaller yet significant number of transposase genes responded (38 total, 28 with increased transcript abundance; Figure 6B, Figure S9), as did a smaller number of DNA repair genes (Figure S10). A similar response was observed in our previous culture-based transcriptomic study, (18) in which N limitation up-regulated a larger number of transposases than did P limitation (21 versus 9; Figure S12). Another recent culture study also suggested that nutrient limitation regulates transposase expression, with transposases from the family IS200/IS605 responding most frequently. (20) Similarly, the majority of transposases with increased transcript abundance in this study were also within the IS605 family (Figures 4A,B and S9). The present study affirms the role of nutrients in influencing the expression of transposase genes and their potential importance in adapting to dynamic biogeochemical conditions in aquatic environments. (63)
Some of the genes identified as transposases have also been putatively assigned roles in phage defense, (66) and it has been hypothesized that phages may act as donors of transposases, thereby contributing to the plasticity of the Microcystis genome. (67) Viruses play a central role in structuring microbial communities and nutrient cycling in aquatic environments. (68-70) Although cyanophages have been implicated as potential drivers of Microcystis bloom demise, (71) investigations of viral infection in Microcystis have reported dramatic initial cell lysis but eventual recovery and resistance to future infections, suggesting resistance among subpopulations and whole-population adaptation. (72) The Microcystis genome contains a remarkably large number of phage defense systems. (66) Of more than 1000 genomes surveyed, Microcystis contained 492 defense genes, or 80% more than Cyanothece PCC8802 or Roseiflexus RS-1 (the next highest), with 29% of its genome assigned to defense islands. (66) Furthermore, the presence of a large diverse number of CRISPR (clustered regularly interspaced short palindromic repeats) spaces within the Microcystis NIES-843 genome suggests this cyanobacterium is frequently infected by viruses. (73) The large and diverse array of viral defense genes is likely an important factor in the continued dominance of this species in freshwater ecosystems. In the current study, when water was amended with P, we observed a large transcriptional response (>250 genes with 167 increasing in transcript abundance) in these phage defense genes, whereas additions of ammonium or urea elicited a smaller response (<70; Figure 6C). Given that viruses have an enhanced ability to replicate when host cells are P-replete, (74) this transcriptomic response by Microcystis suggests P loading increases the frequency with which it is exposed to viruses. Further, these findings indicate that within high-P environments, Microcystis must dedicate more energy toward viral defense and thus may be less likely to dominate cyanobacterial communities.
During this study, a small fraction of transcripts aligned to non-Microcystis cyanobacteria in Lake Erie, likely due to the numerical dominance by Microcystis within most samples as well as genomic mismatches between the organisms found in Lake Erie and available reference genomes. Despite lower mapping rates, transcriptomic trends within Anabaena and Planktothrix genomes evidenced their niche within Lake Erie. For instance, abundance of cells and expressed transcripts for both groups decreased away from the mouth of the nutrient-enriched Maumee River, suggesting the conditions close to the Maumee (high N and P levels) were ideal for these cyanobacteria (Figure 2A; Figure S6). Consistent with these trends, numerous genes involved in photosynthesis and cell division were down-regulated by Anabaena and Planktothrix in the regions away from the Maumee River (a common response to nutrient stress in cyanobacteria), (75) evidencing the physiological basis for their lower abundances (Table 1). Furthermore, the up-regulation of genes involved in degradation of fatty acids by Planktothrix under low-P conditions evidenced a specific energy-sparing mechanism invoked by this genera to subsist in a nutrient-poor environment. (76) Transcriptomic profiling of Anabaena populations revealed that a gene-encoding nitrogenase (nifH) had increased transcript abundance in all stations but LET6 (closest to the high N, Maumee River), indicating its need to fix nitrogen away from high-N regions of Lake Erie (Table 1). During nutrient-amendment experiments, nifH was up-regulated with additions of P, suggesting that additions of P pushed the community further into N limitation. Ammonium also promoted nifH expression. Although high ammonium levels can repress N-fixation, previous work has shown that nitrogenase activity will continue if environmental nitrogen concentrations do not meet cellular N demands. (77, 78) This is likely the case given the low concentrations of ammonium used during the experiment (5 μM) and the relatively large biomass-associated cyanobacterial blooms. (79)

Gene Pathways Facilitating Differential Dominance of Cyanobacteria

Click to copy section linkSection link copied!
Field surveys, experiments, and transcriptomic profiling performed during this study collectively provide insight regarding the specific niches of cyanobacteria across western Lake Erie as well as the genes pathways that facilitate their ability to exploit those niches and form blooms. While Planktothrix and Anabaena dominated the high nutrient environment near the Maumee River, these groups became scarce in more distal regions of the lake and during experiments with lower P concentrations, a pattern also observed across P gradients of the Baltic Sea, where nitrogen-fixing filamentous cyanobacteria dominate high-P regions. (80) The ability of Anabaena to dominate high-P environments is likely related, in part, to its ability to fix N, consistent with the enhanced expression of nifH genes by this taxon when enriched with nutrients. In contrast, enhanced expression of transposases and viral defense genes by Microcystis following P enrichment suggests that synthesis of these proteins, which occupy a substantial portion of the Microcystis genome, (64, 66) represents a significant energy expenditure that may slow its growth within high-P regions. In contrast, Microcystis was the most abundant cyanobacteria in the regions of western Lake Erie with low-P levels and in low-P experimental treatments (i.e., controls or N amendments). The ability of Microcystis to up-regulate genes to efficiently scavenge and store P within P-impoverished zones seemingly provide it with a competitive advantage over other cyanobacteria, allowing it to bloom. Given that Microcystis displayed a gene expression pattern more consistent with N-replete than N-limited conditions, (18) the dominance of Microcystis may be further promoted in particular cases by the enhanced synthesis of grazing deterrents (protease inhibitors) under the relatively higher N levels present in Lake Erie. Clearly, further targeted gene studies are required to better understand the role of individual gene sets in the ecology of cyanobacteria in this and other aquatic ecosystems and to evaluate hypotheses generated during this study. Regardless, the adaptation of Microcystis populations to conditions of low available P and of Anabaena and Planktothrix populations to higher nutrient environments suggests that the development of management schemes to reduce P loads may not significantly reduce the risk of cyanobacterial blooms in Lake Erie. Rather, the reduction of P loads may promote a shift from one cyanobacteria to another and facilitate dominance by more toxic forms (Microcystis). Therefore, managerial schemes that also restrict N inventories may be required to limit the proliferation of nondiazotrophic cyanobacteria such as Microcystis. (81)

Supporting Information

Click to copy section linkSection link copied!

The Supporting Information is available free of charge on the ACS Publications website at DOI: 10.1021/acs.est.5b03931.

  • Tables showing physical, chemical, and community characterizing parameters measured at each station during September and October transects of the western basin of Lake Erie; nutrient concentrations [μM] for each station of the September and October transects of the western basin of Lake Erie; transcriptomic sequencing results; nutrient concentrations [μM] for each treatment for the nutrient amendment experiment; and the number of significantly differentially expressed genes for Microcystis within each functional category relative to the control. Figures showing a composite of MODIS Cyanobacterial Index images from the NOAA Experimental Lake Erie Harmful Algal Bloom Bulletin for 2013; the number of significant differentially expressed genes for Microcystis at each station relative to station LET7 and relative to the control after 48 hr; heat map of genes involved in nitrogen and phosphorous transport and metabolism and their significant differential expression at each station relative to LET7 and under each treatment relative to the control for Microcystis; heat map of transposase genes and their significant differential expression at each station relative to LET7 for Microcystis; cyanobacterial abundance during the October transect of the western basin of Lake Erie for the three genera discussed; the number of significant differentially expressed genes in Planktothrix agaradhii NIVA-CYA 15; the number of significant differentially expressed genes in Anabaena sp. PCC7108; heat map of transposase genes and their significant differential expression relative to the control for Microcystis; heat map of genes involved in DNA replication, restriction, modification, recombination, and repair and their significant differential expression at each station relative to LET7 and under each treatment relative to the control for Microcystis; community analysis via Metaphlan displaying the average percent abundance across two biological replicates for the nutrient enrichment experiments; the number of significant differentially expressed transposase genes. (PDF)

Terms & Conditions

Most electronic Supporting Information files are available without a subscription to ACS Web Editions. Such files may be downloaded by article for research use (if there is a public use license linked to the relevant article, that license may permit other uses). Permission may be obtained from ACS for other uses through requests via the RightsLink permission system: http://pubs.acs.org/page/copyright/permissions.html.

Author Information

Click to copy section linkSection link copied!
  • Corresponding Author
    • Christopher J. Gobler - School of Marine and Atmospheric Sciences, Stony Brook University, Stony Brook, New York 11794, United States;  Email: [email protected]
  • Authors
    • Matthew J. Harke - School of Marine and Atmospheric Sciences, Stony Brook University, Stony Brook, New York 11794, United States
    • Timothy W. Davis - NOAA Great Lakes Environmental Research Laboratory, 4840 S. State Road, Ann Arbor, Michigan 48108, United States
    • Susan B. Watson - Canadian Centre for Inland Waters, Environment Canada, Burlington, Ontario L7R 4A6, Canada
  • Notes
    The authors declare no competing financial interest.

Acknowledgment

Click to copy section linkSection link copied!

We thank Jennifer Goleski for analytical assistance, the captains and crew of the research vessels R/V Erie Monitor and CGS Limnos, and the support staff of The Ohio State University Franz Theodore Stone Laboratory. This work was supported by the NOAA-ECOHAB program being funded by the National Oceanic and Atmospheric Center for Sponsored Coastal Ocean Research under award no. NA10NOS4780140 to Stony Brook University. This study is GLERL contribution number 1790 to the EC Great Lakes Nutrient Initiative (GLNI) and ECOHAB contribution number ECO841.

References

Click to copy section linkSection link copied!

This article references 81 other publications.

  1. 1
    Mortimer, C. H. Fifty years of physical investigations and related limnological studies on Lake Erie, 1928–1977 J. Great Lakes Res. 1987, 13 (4) 407– 435 DOI: 10.1016/S0380-1330(87)71664-5
    Google Scholar
    1
    Fifty years of physical investigations and related limnological studies on Lake Erie, 1928-1977
    Mortimer, C. H.
    Journal of Great Lakes Research (1987), 13 (4), 407-35CODEN: JGLRDE; ISSN:0380-1330.
    The review with 120 refs. covers 50 yr of phys. investigations and related limnol. studies on Lake Erie from 1928 to 1977, including surface surges and seiches, seasonal progression of temp. and O stratification, coupling of thermal stratification with the distribution of O and P in bottom waters, currents with time scale of days or less, sedimentation, and sediment transport.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaL1cXhtlOns74%253D&md5=cc21aa312833e553da60d7c33fd778be
  2. 2
    Rinta-Kanto, J. M.; Ouellette, A. J. A.; Boyer, G. L.; Twiss, M. R.; Bridgeman, T. B.; Wilhelm, S. W. Quantification of toxic Microcystis spp. during the 2003 and 2004 blooms in western Lake Erie using quantitative real-time PCR Environ. Sci. Technol. 2005, 39 (11) 4198– 4205 DOI: 10.1021/es048249u
    Google Scholar
    2
    Quantification of Toxic Microcystis spp. during the 2003 and 2004 Blooms in Western Lake Erie using Quantitative Real-Time PCR
    Rinta-Kanto, J. M.; Ouellette, A. J. A.; Boyer, G. L.; Twiss, M. R.; Bridgeman, T. B.; Wilhelm, S. W.
    Environmental Science and Technology (2005), 39 (11), 4198-4205CODEN: ESTHAG; ISSN:0013-936X. (American Chemical Society)
    In August of 2003 and August of 2004, blooms of potentially toxic cyanobacteria Microcystis spp. persisted in western Lake Erie. Samples collected from the bloom were analyzed for the cyanobacterial toxin microcystin and the presence of Microcystis spp. cells. Ests. of microcystin toxicity exceeding 1 μg L-1 (microcystin-LR activity equiv.), the safety limit set by the World Health Organization, were found from the samples in both 2003 and 2004. The presence of Microcystis spp. in water samples was confirmed through std. polymerase chain reaction (PCR) using a combination of four primer sets. Quantification of Microcystis was accomplished by a real-time PCR assay utilizing specific primer-Taq-man probe sets targeted on a conserved, Microcystis-specific 16S rDNA fragment and a microcystin toxin synthetase gene mcyD. This approach allowed us to specifically study the distribution and abundance of toxic Microcystis in the lake in contrast to previous studies that have assessed Microcystis populations with less refined methods. On the basis of quantification by quant. real-time PCR anal., the total abundance of Microcystis cells in the bloom area varied from 4 × 108 to 2 × 103 cells L-1. The results of this study provide novel insight regarding the distribution and abundance of Microcystis spp. in the western basin of Lake Erie, a region plagued in recent years by large-scale (>20 km2) blooms. Our results suggest that the Maumee River and Bay may serve as a source for Microcystis to western and central Lake Erie.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD2MXjsVGgs7k%253D&md5=59ee5f109d38e7c0c06ed416e62cdd6c
  3. 3
    Bridgeman, T. B.; Chaffin, J. D.; Kane, D. D.; Conroy, J. D.; Panek, S. E.; Armenio, P. M. From River to Lake: Phosphorus partitioning and algal community compositional changes in Western Lake Erie J. Great Lakes Res. 2012, 38, 90– 97 DOI: 10.1016/j.jglr.2011.09.010
    Google Scholar
    3
    From river to lake: Phosphorus partitioning and algal community compositional changes in Western Lake Erie
    Bridgeman, Thomas B.; Chaffin, Justin D.; Kane, Douglas D.; Conroy, Joseph D.; Panek, Sarah E.; Armenio, Patricia M.
    Journal of Great Lakes Research (2012), 38 (1), 90-97CODEN: JGLRDE; ISSN:0380-1330. (Elsevier B.V.)
    The Maumee River is an important source of phosphorus (P) loading to western Lake Erie and potentially a source of Microcystis seed colonies contributing to the development of harmful algal blooms in the lake. Herein, we quantified P forms and size fractions, and phytoplankton community compn. in the river-lake coupled ecosystem before (June), during (August), and after (Sept.) a large Microcystis bloom in 2009. Addnl., we detd. the distribution and d. of a newly emergent cyanobacterium, Lyngbya wollei, near Maumee Bay to est. potential P sequestration. In June, dissolved org. phosphorus (DOP) was the most abundant P form whereas particulate P (partP) was most abundant in August and Sept. Green algae dominated in June (44% and 60% of total chlorophyll in river and lake, resp.) with substantial Microcystis (17%) present only in the river. Conversely, in August, Microcystis declined in the river (3%) but dominated (32%) the lake. Lake phytoplankton sequestered < 6% of water column P even during peak Microcystis blooms; in all lake samples < 112 μm non-algal particles dominated partP. Lyngbya d. averaged 19.4 g dry wt/m2, with av. Lyngbya P content of 15% (to 75% max.) of water column P. The presence of Microcystis in the river before appearing in the lake indicates that the river is a potential source of Microcystis seed colonies for later lake blooms, that DOP is an important component of early summer total P, and that L. wollei blooms have the potential to increase P retention in nearshore areas.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC38Xis1entLc%253D&md5=9ebad620f55d193dd6af5a6d239f5611
  4. 4
    Stumpf, R. P.; Wynne, T. T.; Baker, D. B.; Fahnenstiel, G. L. Interannual variability of cyanobacterial blooms in Lake Erie PLoS One 2012, 7 (8) e42444 DOI: 10.1371/journal.pone.0042444
    Google Scholar
    4
    Interannual variability of cyanobacterial blooms in Lake Erie
    Stumpf, Richard P.; Wynne, Timothy T.; Baker, David B.; Fahnenstiel, Gary L.
    PLoS One (2012), 7 (8), e42444CODEN: POLNCL; ISSN:1932-6203. (Public Library of Science)
    After a 20-yr absence, severe cyanobacterial blooms have returned to Lake Erie in the last decade, in spite of negligible change in the annual load of total phosphorus (TP). Medium-spectral Resoln. Imaging Spectrometer (MERIS) imagery was used to quantify intensity of the cyanobacterial bloom for each year from 2002 to 2011. The blooms peaked in August or later, yet correlate to discharge (Q) and TP loads only for March through June. The influence of the spring TP load appears to have started in the late 1990 s, after Dreissenid mussels colonized the lake, as hindcasts prior to 1998 are inconsistent with the obsd. blooms. The total spring Q or TP load appears sufficient to predict bloom magnitude, permitting a seasonal forecast prior to the start of the bloom.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC38XhtFKhtrvE&md5=cddba20afbce2a22595c46ed6c758f73
  5. 5
    Dolan, D. M.; Chapra, S. C. Great Lakes total phosphorus revisited: 1. Loading analysis and update (1994–2008) J. Great Lakes Res. 2012, 38 (4) 730– 740 DOI: 10.1016/j.jglr.2012.10.001
    Google Scholar
    5
    Great Lakes total phosphorus revisited: 1. Loading analysis and update (1994-2008)
    Dolan, David M.; Chapra, Steven C.
    Journal of Great Lakes Research (2012), 38 (4), 730-740CODEN: JGLRDE; ISSN:0380-1330. (Elsevier B.V.)
    A review. Phosphorus load ests. have been updated for all of the Great Lakes with an emphasis on lakes Superior, Michigan, Huron and Ontario for 1994-2008. Lake Erie phosphorus loads have been kept current with previous work and for completeness are reported here. A combination of modeling and data anal. is employed to evaluate whether target loads established by the Great Lakes Water Quality Agreement (GLWQA, 1978, Annex 3) have been and are currently being met. Data from federal, state, and provincial agencies were assembled and processed to yield annual ests. for all lakes and sources. A mass-balance model was used to check the consistency of loads and to est. interlake transport. The anal. suggests that the GLWQA target loads have been consistently met for the main bodies of lakes Superior, Michigan and Huron. However, exceedances still persist for Saginaw Bay. For lakes Erie and Ontario, loadings are currently estd. to be at or just under the target (with some notable exceptions). Because interannual variability is high, the target loads have not been met consistently for the lower Great Lakes. The anal. also indicates that, because of decreasing TP concns. in the lakes, interlake transport of TP has declined significantly since the mid-1970s. Thus, it is important that these changes be included in future assessments of compliance with TP load targets. Finally, detailed tables of the yearly (1994-2008) ests. are provided, as well as annual summaries by lake tributary basin (in Supplementary Information).
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC38XhslSltbfO&md5=d8032e9aa9cbd7f89577ccd7657bd592
  6. 6
    Han, H.; Allan, J. D.; Bosch, N. S. Historical pattern of phosphorus loading to Lake Erie watersheds J. Great Lakes Res. 2012, 38, 289– 298 DOI: 10.1016/j.jglr.2012.03.004
    Google Scholar
    6
    Historical pattern of phosphorus loading to Lake Erie watersheds
    Han, Haejin; Allan, J. David; Bosch, Nathan S.
    Journal of Great Lakes Research (2012), 38 (2), 289-298CODEN: JGLRDE; ISSN:0380-1330. (Elsevier B.V.)
    Phosphorus (P) applied to croplands in excess of crop requirements has resulted in large-scale accumulation of P in soils worldwide, leading to freshwater eutrophication from river runoff that may extend well into the future. However, several studies have reported declines in surplus P inputs to the land in recent decades. To quantify trends in P loading to Lake Erie (LE) watersheds, we estd. net anthropogenic phosphorus inputs (NAPI) to 18 LE watersheds for agricultural census years from 1935 to 2007. NAPI quantifies anthropogenic inputs of P from fertilizer use, atm. deposition and detergents, as well as the net exchange in P related to trade in food and feed. Over this 70-yr period, NAPI increased to peak values in the 1970s and subsequently declined in 2007 to a level last experienced in 1935. This rise and fall was the result of two trends: a dramatic increase in fertilizer use, which peaked in the 1970s and then declined to about two-thirds of max. values; and a steady increase in P exported as crops destined for animal feed and energy prodn. During 1974-2007, riverine phosphorus loads fluctuated, and were correlated with inter-annual variation in water discharge. However, riverine P export did not show consistent temporal trends, nor correlate with temporal trends in NAPI or fertilizer use. The fraction of P inputs exported by rivers appeared to increase sharply after the 1990s, but the cause is unknown. Thus ests. of phosphorus inputs to watersheds provide insight into changing source quantities but may be weak predictors of riverine export.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC38XmvFegtr4%253D&md5=73a2bb8372540a8858473097c2b4fa16
  7. 7
    Michalak, A. M.; Anderson, E. J.; Beletsky, D.; Boland, S.; Bosch, N. S.; Bridgeman, T. B.; Chaffin, J. D.; Cho, K.; Confesor, R.; Daloglu, I.; Depinto, J. V.; Evans, M. A.; Fahnenstiel, G. L.; He, L.; Ho, J. C.; Jenkins, L.; Johengen, T. H.; Kuo, K. C.; Laporte, E.; Liu, X.; McWilliams, M. R.; Moore, M. R.; Posselt, D. J.; Richards, R. P.; Scavia, D.; Steiner, A. L.; Verhamme, E.; Wright, D. M.; Zagorski, M. A. Record-setting algal bloom in Lake Erie caused by agricultural and meteorological trends consistent with expected future conditions Proc. Natl. Acad. Sci. U. S. A. 2013, 110 (16) 6448– 52 DOI: 10.1073/pnas.1216006110
    Google Scholar
    7
    Record-setting algal bloom in Lake Erie caused by agricultural and meteorological trends consistent with expected future conditions
    Michalak, Anna M.; Anderson, Eric J.; Beletsky, Dmitry; Boland, Steven; Bosch, Nathan S.; Bridgeman, Thomas B.; Chaffin, Justin D.; Cho, Kyunghwa; Confesor, Rem; Daloglu, Irem; DePinto, Joseph V.; Evans, Mary Anne; Fahnenstiel, Gary L.; He, Lingli; Ho, Jeff C.; Jenkins, Liza; Johengen, Thomas H.; Kuo, Kevin C.; LaPorte, Elizabeth; Liu Xiaojian; McWilliams, Michael R.; Moore, Michael R.; Posselt, Derek J.; Richards, R. Peter; Scavia, Donald; Steiner, Allison L.; Verhamme, Ed; Wright, David M.; Zagorski, Melissa A.
    Proceedings of the National Academy of Sciences of the United States of America (2013), 110 (16), 6448-6452, S6448/1-S6448/14CODEN: PNASA6; ISSN:0027-8424. (National Academy of Sciences)
    In 2011, Lake Erie experienced the largest harmful algal bloom in its recorded history, with a peak intensity over 3 times greater than any previously obsd. bloom. We show that long-term trends in agricultural practices are consistent with increasing P loading to the western basin of the lake, and that these trends, coupled with meteorol. conditions in spring 2011, produced record-breaking nutrient loads. An extended period of weak lake circulation then led to abnormally long residence times that incubated the bloom, and warm and quiescent conditions after bloom onset allowed algae to remain near the top of the water column and prevented flushing of nutrients from the system. We further find that all of these factors are consistent with expected future conditions. If a scientifically guided management plan to mitigate these impacts is not implemented, we can therefore expect this bloom to be a harbinger of future blooms in Lake Erie.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3sXnvVelsbo%253D&md5=56b087980adef31dfcd87aa306024d1e
  8. 8
    Murphy, T. P.; Irvine, K.; Guo, J.; Davies, J.; Murkin, H.; Charlton, M.; Watson, S. B. New microcystin concerns in the lower great lakes Water Qual. Res. J. Canada 2003, 38 (1) 127– 140
    Google Scholar
    8
    New microcystin concerns in the lower great lakes
    Murphy, Tom P.; Irvine, Kim; Guo, Jay; Davies, John; Murkin, Henry; Charlton, Murray; Watson, Susan B.
    Water Quality Research Journal of Canada (2003), 38 (1), 127-140CODEN: WQRCFA; ISSN:1201-3080. (Canadian Association on Water Quality)
    Water samples were collected in summer 2001 for microcystin anal., nutrient detn., and algal enumeration from Hamilton Harbor (Lake Ontario), Wendt Beach and Presque Isle (Lake Erie). Microcystin concns. varied largely and were present at acute toxicity levels only in some wind-concd. blue-green algae scums (>90% Microcystis, primarily M. botrys, M. viridis, and some M. wesenbergii) in Hamilton Harbor. In Hamilton Harbor, microcystin-RR was the main microcystin with microcystin-YR and -LR also present. Samples on August 17 and Sept. 7, collected during at the peak of the cyanobacterial bloom, contained 60 and 400 μg/L, resp. Several dying birds were obsd. in the Hamilton scums. Microcystin concns. at the Lake Erie sites were <1 μg/L, yet dead birds were common. The major limitation with this approach is that current anal. (ELISA and HPLC) methods cannot measure covalently-bound microcystins, the form assimilated into the food chain.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD3sXitFWntbo%253D&md5=1040da4666cb91c6ebd62154e4ddf376
  9. 9
    Gallo, A. Algae blooms making Toledo water undrinkable are thriving. Wall Street Journal, August 3, 2014.
    Google Scholar
    There is no corresponding record for this reference.
  10. 10
    Elser, J. J.; Bracken, M. E.; Cleland, E. E.; Gruner, D. S.; Harpole, W. S.; Hillebrand, H.; Ngai, J. T.; Seabloom, E. W.; Shurin, J. B.; Smith, J. E. Global analysis of nitrogen and phosphorus limitation of primary producers in freshwater, marine and terrestrial ecosystems Ecology Letters 2007, 10 (12) 1135– 42 DOI: 10.1111/j.1461-0248.2007.01113.x
    Google Scholar
    10
    Global analysis of nitrogen and phosphorus limitation of primary producers in freshwater, marine and terrestrial ecosystems
    Elser James J; Bracken Matthew E S; Cleland Elsa E; Gruner Daniel S; Harpole W Stanley; Hillebrand Helmut; Ngai Jacqueline T; Seabloom Eric W; Shurin Jonathan B; Smith Jennifer E
    Ecology letters (2007), 10 (12), 1135-42 ISSN:.
    The cycles of the key nutrient elements nitrogen (N) and phosphorus (P) have been massively altered by anthropogenic activities. Thus, it is essential to understand how photosynthetic production across diverse ecosystems is, or is not, limited by N and P. Via a large-scale meta-analysis of experimental enrichments, we show that P limitation is equally strong across these major habitats and that N and P limitation are equivalent within both terrestrial and freshwater systems. Furthermore, simultaneous N and P enrichment produces strongly positive synergistic responses in all three environments. Thus, contrary to some prevailing paradigms, freshwater, marine and terrestrial ecosystems are surprisingly similar in terms of N and P limitation.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A280%3ADC%252BD2snmtlCntA%253D%253D&md5=2cfe209973178bbd904f7c3829f18d49
  11. 11
    Schindler, D. W. Evolution of phosphorus limitation in lakes Science 1977, 195 (4275) 260– 262 DOI: 10.1126/science.195.4275.260
    Google Scholar
    11
    Evolution of phosphorus limitation in lakes
    Schindler, D. W.
    Science (Washington, DC, United States) (1977), 195 (4275), 260-2CODEN: SCIEAS; ISSN:0036-8075.
    The nutrient-control question of lakes is reexamd. Evidence for C and N as alternatives to P as limiting nutrients are considered.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaE2sXht1Kqt78%253D&md5=8b9b6be527db8f82cfe09a27eb4f9e24
  12. 12
    Steffen, M. M.; Belisle, B. S.; Watson, S. B.; Boyer, G. L.; Wilhelm, S. W. Status, causes and controls of cyanobacterial blooms in Lake Erie J. Great Lakes Res. 2014, 40 (2) 215– 225 DOI: 10.1016/j.jglr.2013.12.012
    Google Scholar
    12
    Status, causes and controls of cyanobacterial blooms in Lake Erie
    Steffen, Morgan M.; Belisle, B. Shafer; Watson, Sue B.; Boyer, Gregory L.; Wilhelm, Steven W.
    Journal of Great Lakes Research (2014), 40 (2), 215-225CODEN: JGLRDE; ISSN:0380-1330. (Elsevier B.V.)
    A review. The Laurentian Great Lakes are among the most prominent sources of fresh water in the world. Lake Erie's infamous cyanobacterial blooms have, however, threatened the health of this valuable freshwater resource for decades. Toxic blooms dominated by the cyanobacterium Microcystis aeruginosa have most recently been one of primary ecol. concerns for the lake. These toxic blooms impact the availability of potable water, as well as public health and revenues from the tourism and fishery industries. The socioeconomic effects of these blooms have spurred research efforts to pinpoint factors that drive bloom events. Despite decades of research and mitigation efforts, these blooms have expanded both in size and duration in recent years. However, through continued joint efforts between the Canadian and United States governments, scientists, and environmental managers, identification of the factors that drive bloom events is within reach. This review provides a summary of historical and contemporary research efforts in the realm of Lake Erie's harmful cyanobacterial blooms, both in terms of exptl. and management achievements and insufficiencies, as well as future directions on the horizon for the lake's research community.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2cXhtlGrurw%253D&md5=6bf5ad4454d30d67d5754d9916ae87aa
  13. 13
    Chaffin, J. D.; Bridgeman, T. B.; Bade, D. L. Nitrogen Constrains the Growth of Late Summer Cyanobacterial Blooms in Lake Erie Adv. Microbiol. 2013, 3, 16– 26 DOI: 10.4236/aim.2013.36A003
    Google Scholar
    13
    Nitrogen constrains the growth of late summer cyanobacterial blooms in Lake Erie
    Chaffin, Justin D.; Bridgeman, Thomas B.; Bade, Darren L.
    Advances in Microbiology (2013), 3 (6), 16-26CODEN: AMDIFS; ISSN:2165-3410. (Scientific Research Publishing, Inc.)
    Phosphorus (P) is generally considered to be the main limiting nutrient to freshwater phytoplankton productivity. However, recent research is drawing attention to the importance of nitrogen (N) in freshwater eutrophication and N often constrains growth of cyanobacteria in small lakes. In this study we detd. phytoplankton nutrient limitation in a large lake, Lake Erie during two growing seasons. During 2010 and 2011, nutrient enrichment bioassays (+P, +N and, +P and N) were conducted monthly from June through Sept. with water collected in Maumee Bay (site MB18) and in the center of the western basin (site WBC). Nutrient concns. were monitored every other week. At MB18, total P concn. was often >3 μmol/L and nitrate concn. decreased from >250 μmol/L in early summer to <1 μmol/L in late summer. Nitrogen and P levels were about five-fold less at WBC. Bioassays indicated that phyto-plankton nutrient limitation varied in summer, spatially, and even among phytoplankton groups. For site MB18, +P in-creased chlorophyll concn. in one of the eight bioassays, indicating that P did not typically limit prodn. For site WBC, +P increased chlorophyll concn. in six of the eight bioassays. As a result of very low ambient nitrate concn. (<5 μmol/L) in late summer, +N (without P) increased chlorophyll concn., suggesting symptoms of N-limitation. The N-fixing cyanobacterium Anabaena became dominant following N-limitation. This study high-lights the need to reduce P loading to restore water quality. Furthermore, due to low nitrate concn., the severity of the cyanobacterial blooms could be worse if not for N-limitation in western Lake Erie.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2cXltlOiu7k%253D&md5=dd8373dcd446cd4e46c312253d6530e7
  14. 14
    Davis, T. W.; Harke, M. J.; Marcoval, M. A.; Goleski, J.; Orano-Dawson, C.; Berry, D. L.; Gobler, C. J. Effects of nitrogenous compounds and phosphorus on the growth of toxic and non-toxic strains of Microcystis during cyanobacterial blooms Aquat. Microb. Ecol. 2010, 61, 149– 162 DOI: 10.3354/ame01445
    Google Scholar
    There is no corresponding record for this reference.
  15. 15
    Rinta-Kanto, J. M.; Konopko, E. A.; DeBruyn, J. M.; Bourbonniere, R. A.; Boyer, G. L.; Wilhelm, S. W. Lake Erie Microcystis: Relationship between microcystin production, dynamics of genotypes and environmental parameters in a large lake Harmful Algae 2009, 8 (5) 665– 673 DOI: 10.1016/j.hal.2008.12.004
    Google Scholar
    There is no corresponding record for this reference.
  16. 16
    Davis, T. W.; Watson, S. B.; Rozmarynowycz, M. J.; Ciborowski, J. J. H.; McKay, R. M.; Bullerjahn, G. S. Phylogenies of microcystin-producing cyanobacteria in the lower Laurentian Great Lakes suggest extensive genetic connectivity PLoS One 2014, 9 (9) e106093 DOI: 10.1371/journal.pone.0106093
    Google Scholar
    There is no corresponding record for this reference.
  17. 17
    Steffen, M. M.; Li, Z.; Effler, T. C.; Hauser, L. J.; Boyer, G. L.; Wilhelm, S. W. Comparative Metagenomics of Toxic Freshwater Cyanobacteria Bloom Communities on Two Continents PLoS One 2012, 7 (8) e44002 DOI: 10.1371/journal.pone.0044002
    Google Scholar
    17
    Comparative metagenomics of toxic freshwater Cyanobacteria bloom communities on two continents
    Steffen, Morgan M.; Li, Zhou; Effler, T. Chad; Hauser, Loren J.; Boyer, Gregory L.; Wilhelm, Steven W.
    PLoS One (2012), 7 (8), e44002CODEN: POLNCL; ISSN:1932-6203. (Public Library of Science)
    Toxic cyanobacterial blooms have persisted in freshwater systems around the world for centuries and appear to be globally increasing in frequency and severity. Toxins produced by bloom-assocd. cyanobacteria can have drastic impacts on the ecosystem and surrounding communities, and bloom biomass can disrupt aquatic food webs and act as a driver for hypoxia. Little is currently known regarding the genomic content of the Microcystis strains that form blooms or the companion heterotrophic community assocd. with bloom events. To address these issues, we examd. the bloom-assocd. microbial communities in single samples from Lake Erie (North America), Lake Tai (Taihu, China), and Grand Lakes St. Marys (OH, USA) using comparative metagenomics. Together the Cyanobacteria and Proteobacteria comprised >90% of each bloom bacterial community sample, although the dominant phylum varied between systems. Relative to the existing Microcystis aeruginosa NIES 843 genome, sequences from Lake Erie and Taihu revealed a no. of metagenomic islands that were absent in the environmental samples. Moreover, despite variation in the phylogenetic assignments of bloom-assocd. organisms, the functional potential of bloom members remained relatively const. between systems. This pattern was particularly noticeable in the genomic contribution of nitrogen assimilation genes. In Taihu, the genetic elements assocd. with the assimilation and metab. of nitrogen were predominantly assocd. with Proteobacteria, while these functions in the North American lakes were primarily contributed to by the Cyanobacteria. Our observations build on an emerging body of metagenomic surveys describing the functional potential of microbial communities as more highly conserved than that of their phylogenetic makeup within natural systems.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC38Xht12ht7jP&md5=cd12caa1688338a607fafb3d539ada4f
  18. 18
    Harke, M. J.; Gobler, C. J. Global transcriptional responses of the toxic cyanobacterium, Microcystis aeruginosa, to nitrogen stress, phosphorus stress, and growth on organic matter PLoS One 2013, 8 (7) e69834 DOI: 10.1371/journal.pone.0069834
    Google Scholar
    18
    Global transcriptional responses of the toxic cyanobacterium, Microcystis aeruginosa, to nitrogen stress, phosphorus stress, and growth on organic matter
    Harke, Matthew J.; Gobler, Christopher J.
    PLoS One (2013), 8 (7), e69834CODEN: POLNCL; ISSN:1932-6203. (Public Library of Science)
    Whole transcriptome shotgun sequencing (RNA-seq) was used to assess the transcriptomic response of the toxic cyanobacterium Microcystis aeruginosa during growth with low levels of dissolved inorg. nitrogen (low N), low levels of dissolved inorg. phosphorus (low P), and in the presence of high levels of high mol. wt. dissolved org. matter (HMWDOM). Under low N, one third of the genome was differentially expressed, with significant increases in transcripts obsd. among genes within the nir operon, urea transport genes (urtBCDE), and amino acid transporters while significant decreases in transcripts were obsd. in genes related to photosynthesis. There was also a significant decrease in the transcription of the microcystin synthetase gene set under low N and a significant decrease in microcystin content per Microcystis cell demonstrating that N supply influences cellular toxicity. Under low P, 27% of the genome was differentially expressed. The Pho regulon was induced leading to large increases in transcript levels of the alk. phosphatase phoX, the Pst transport system (pstABC), and the sphX gene, and transcripts of multiple sulfate transporter were also significantly more abundant. While the transcriptional response to growth on HMWDOM was smaller (5-22 % of genes differentially expressed), transcripts of multiple genes specifically assocd. with the transport and degrdn. of org. compds. were significantly more abundant within HMWDOM treatments and thus may be recruited by Microcystis to utilize these substrates. Collectively, these findings provide a comprehensive understanding of the nutritional physiol. of this toxic, bloom-forming cyanobacterium and the role of N in controlling microcystin synthesis.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3sXht1ersLjK&md5=ef180850728657830bcf2299973e4902
  19. 19
    Straub, C.; Quillardet, P.; Vergalli, J.; de Marsac, N. T.; Humbert, J.-F. A day in the life of Microcystis aeruginosa strain PCC 7806 as revealed by a transcriptomic analysis PLoS One 2011, 6 (1) e16208 DOI: 10.1371/journal.pone.0016208
    Google Scholar
    There is no corresponding record for this reference.
  20. 20
    Steffen, M. M.; Dearth, S. P.; Dill, B. D.; Li, Z.; Larsen, K. M.; Campagna, S. R.; Wilhelm, S. W. Nutrients drive transcriptional changes that maintain metabolic homeostasis but alter genome architecture in Microcystis ISME J. 2014, 8 (10) 2080– 92 DOI: 10.1038/ismej.2014.78
    Google Scholar
    20
    Nutrients drive transcriptional changes that maintain metabolic homeostasis but alter genome architecture in Microcystis
    Steffen, Morgan M.; Dearth, Stephen P.; Dill, Brian D.; Li, Zhou; Larsen, Kristen M.; Campagna, Shawn R.; Wilhelm, Steven W.
    ISME Journal (2014), 8 (10), 2080-2092CODEN: IJSOCF; ISSN:1751-7362. (Nature Publishing Group)
    The cyanobacterium Microcystis aeruginosa is a globally distributed bloom-forming organism that degrades freshwater systems around the world. Factors that drive its dispersion, diversification and success remain, however, poorly understood. To develop insight into cellular-level responses to nutrient drivers of eutrophication, RNA sequencing was coupled to a comprehensive metabolomics survey of M. aeruginosa sp. NIES 843 grown in various nutrient-reduced conditions. Transcriptomes were generated for cultures grown in nutrient-replete (with nitrate as the nitrogen (N) source), nitrogen-reduced (with nitrate, urea or ammonium acting as the N sources) and phosphate-reduced conditions. Extensive expression differences (up to 696 genes for urea-grown cells) relative to the control treatment were obsd., demonstrating that the chem. variant of nitrogen available to cells affected transcriptional activity. Of particular note, a high no. of transposase genes (up to 81) were significantly and reproducibly up-regulated relative to the control when grown on urea. Conversely, phosphorus (P) redn. resulted in a significant cessation in transcription of transposase genes, indicating that variation in nutrient chem. may influence transcription of transposases and may impact the highly mosaic genomic architecture of M. aeruginosa. Corresponding metabolomes showed comparably few differences between treatments, suggesting broad changes to gene transcription are required to maintain metabolic homeostasis under nutrient redn. The combined observations provide novel and extensive insight into the complex cellular interactions that take place in this important bloom-forming organism during variable nutrient conditions and highlight a potential unknown mol. mechanism that may drive Microcystis blooms and evolution.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2cXhs1Squ73I&md5=9d6dd595ea07c7f3874b1f10c9747828
  21. 21
    Beutler, M.; Wiltshire, K. H.; Meyer, B.; Moldaenke, C.; Lüring, C.; Meyerhöfer, M.; Hansen, U. P.; Dau, H. A fluorometric method for the differentiation of algal populations in vivo and in situ Photosynth. Res. 2002, 72 (1) 39– 53 DOI: 10.1023/A:1016026607048
    Google Scholar
    21
    A fluorometric method for the differentiation of algal populations in vivo and in situ
    Beutler, M.; Wiltshire, K. H.; Meyer, B.; Moldaenke, C.; Luering, C.; Meyerhoefer, M.; Hansen, U.-P.; Dau, H.
    Photosynthesis Research (2002), 72 (1), 39-53CODEN: PHRSDI; ISSN:0166-8595. (Kluwer Academic Publishers)
    Fingerprints of excitation spectra of chlorophyll (Chl) fluorescence can be used to differentiate 'spectral groups' of microalgae in vivo and in situ in, for example, vertical profiles within a few seconds. The investigated spectral groups of algae (green group, Chlorophyta; blue, Cyanobacteria; brown, Heterokontophyta, Haptophyta, Dinophyta; mixed, Cryptophyta) are each characterized by a specific compn. of photosynthetic antenna pigments and, consequently, by a specific excitation spectrum of the Chl fluorescence. Particularly relevant are Chl a, Chl c, phycocyanobilin, phycoerythrobilin, fucoxanthin and peridinin. A lab.-based instrument and a submersible instrument were constructed contg. light-emitting diodes to excite Chl fluorescence in five distinct wavelength ranges. Norm spectra were detd. for the four spectral algal groups (several species per group). Using these norm spectra and the actual five-point excitation spectrum of a water sample, a sep. est. of the resp. Chl concn. is rapidly obtained for each algal group. The results of diln. expts. are presented. In vivo and in situ measurements are compared with results obtained by HPLC anal. Depth profiles of the distribution of spectral algal groups taken over a time period of few seconds are shown. The method for algae differentiation described here opens up new research areas, monitoring and supervision tasks related to photosynthetic primary prodn. in aquatic environments.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD38XkvFejsb4%253D&md5=699e5fd2845e29c7c5abc73c49aba8e2
  22. 22
    Jones, M. N. Nitrate reduction by shaking with cadmium: Alternative to cadmium columns Water Res. 1984, 18, 643– 646 DOI: 10.1016/0043-1354(84)90215-X
    Google Scholar
    22
    Nitrate reduction by shaking with cadmium. Alternative to cadmium columns
    Jones, Martha N.
    Water Research (1984), 18 (5), 643-6CODEN: WATRAG; ISSN:0043-1354.
    In a manual method, small vol. water samples buffered at pH 8.5 are shaken for ∼90 min with spongy Cd to reduce NO3- to NO2-, which is detd. colorimetrically. Contact time between sample and Cd is more consistently controlled for simultaneous anal. of a large series of samples than in a column method and avoids progressive and unequal deterioration of Cd redn. capacity. Shaking 60-90 min completely reduced concns. of NO3- of 1-100 μM.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaL2cXhvFOmsL8%253D&md5=c8c3057b14a3b2f422eb4a3192e6e1db
  23. 23
    Parsons, T. R.; Maita, Y.; Lalli, C. M. A Manual of Chemical and Biological Methods for Seawater Analysis. Pergamon Press: Oxford, 1984.
    Google Scholar
    There is no corresponding record for this reference.
  24. 24
    Valderrama, J. C. The simultaneous analysis of total nitrogen and phosphorus in natural waters Mar. Chem. 1981, 10, 109– 122 DOI: 10.1016/0304-4203(81)90027-X
    Google Scholar
    There is no corresponding record for this reference.
  25. 25
    Simis, S. G. H.; Huot, Y.; Babin, M.; Seppälä, J.; Metsamaa, L. Optimization of variable fluorescence measurements of phytoplankton communities with cyanobacteria Photosynth. Res. 2012, 112, 13– 30 DOI: 10.1007/s11120-012-9729-6
    Google Scholar
    25
    Optimization of variable fluorescence measurements of phytoplankton communities with cyanobacteria
    Simis, Stefan G. H.; Huot, Yannick; Babin, Marcel; Seppaelae, Jukka; Metsamaa, Liisa
    Photosynthesis Research (2012), 112 (1), 13-30CODEN: PHRSDI; ISSN:0166-8595. (Springer)
    Excitation-emission fluorescence matrixes of phytoplankton communities were simulated from lab.-grown algae and cyanobacteria cultures, to define the optical configurations of theor. fluorometers that either minimize or maximize the representation of these phytoplankton groups in community variable fluorescence measurements. Excitation sources that match the photosystem II (PSII) action spectrum of cyanobacteria do not necessarily lead to equal representation of cyanobacteria in community fluorescence. In communities with an equal share of algae and cyanobacteria, inducible PSII fluorescence in algae can be retrieved from community fluorescence under blue excitation (450-470 nm) with high accuracy (R 2 = 1.00). The highest correlation between community and cyanobacterial variable fluorescence is obtained under orange-red excitation in the 590-650 nm range (R 2 = 0.54). Gaussian band decompn. reveals that in the presence of cyanobacteria, the emission detection slit must be narrow (up to 10 nm) and centered on PSII chlorophyll-a emission (~683 nm) to avoid severe dampening of the signal by weakly variable phycobilisomal fluorescence and non-variable photosystem I fluorescence. When these optimizations of the optical configuration of the fluorometer are followed, both cyanobacterial and algal cultures in nutrient replete exponential growth exhibit values of the max. quantum yield of charge sepn. in PSII in the range of 0.65-0.7.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC38XltlKjsb4%253D&md5=3c634869bd8dfb453eee20fd46d3629e
  26. 26
    Rattan, K. J. An inter-basin comparison of nutrient limitation and the irradiance response of pulse-amplitude modulated (PAM) fluorescence in Lake Erie phytoplankton Aquat. Ecol. 2014, 48 (1) 107– 125 DOI: 10.1007/s10452-014-9470-7
    Google Scholar
    26
    An inter-basin comparison of nutrient limitation and the irradiance response of pulse-amplitude modulated (PAM) fluorescence in Lake Erie phytoplankton
    Rattan, K. J.
    Aquatic Ecology (2014), 48 (1), 107-125CODEN: AQECF9; ISSN:1386-2588. (Springer)
    This research examd. the application of the max. quantum efficiency (Fv/Fm) and relative electron transport rate vs. irradiance curves (rETR) as a rapid, sensitive assessment of Lake Erie phytoplankton nutrient status. I evaluated the potential benefits of the variable fluorescence parameters by comparing these parameters with chem. and physiol. nutrient status assays. I tested the hypothesis that Fv/Fm and rETR curves could diagnose nutrient status in natural lake phytoplankton and be capable of discriminating which inorg. nutrient is limited temporally and spatially. Fv/Fm was on av. highest in the more eutrophic west basin (WB) and lowest in the more oligotrophic central basin (CB). According to the chem. and physiol. indicators, P deficiency was most severe in the CB during summer stratification and N deficiency was strongest in the WB during isothermal conditions. Like Fv/Fm, rETR at light satn. (rETRmax) and the initial slope of the rETR vs. irradiance curve (α) decreased as the severity of N and P deficiency increased. Amendment with N or P stimulated increased Fv/Fm, rETRmax, and α in N- and P-limited samples, resp., and abolished the photoinhibition apparent in rETR curves of nutrient-limited samples. These results supported the view that the N and P deficiency assays, and corresponding variations of variable fluorescence parameters, were valid indicators of widely variable N and P deficiency in the phytoplankton, and could be used to provide a promising tool in detg. phytoplankton nutrient status. Contrary to my hopes, it did not appear that rETR-irradiance curves could discriminate between N and P deficiency. Identification of the most limiting nutrient still demanded addnl. information beyond the variable fluorescence measurements.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2cXjtlCls7s%253D&md5=6642a6270e7986003d7ee8f7ca0ed443
  27. 27
    Hoppe, H. G. Significance of exoenzymatic activities in the ecology of brackish water: measurements by means of methylumbelliferyl-substrates Mar. Ecol.: Prog. Ser. 1983, 11 (3) 299– 308 DOI: 10.3354/meps011299
    Google Scholar
    27
    Significance of exoenzymatic activities in the ecology of brackish water: measurements by means of methylumbelliferyl substrates
    Hoppe, Hans Georg
    Marine Ecology: Progress Series (1983), 11 (3), 299-308CODEN: MESEDT; ISSN:0171-8630.
    The rates of hydrolysis of glucosides, protein-like compds., glucosaminides, and org. phosphorus compds., as well as hydrolyzation rates of naturally occurring substrate analogs were measured using fluorogenic methylumbelliferyl (I) compds. in 2 eutrophic Baltic Sea fjords and adjacent offshore waters. The activity of protease [9001-92-7] was dominant in all water samples. The activity of α-D-glucosidase [9033-06-1] and glucosaminidase [76199-21-8] varied significantly between fjords and offshore waters. An expt. with I compds. and radioactively labeled substrates indicated there is a discrepancy between the amt. of substrate hydrolyzed by exoenzymes and the amt. incorporated by bacteria. This suggests that there are medium-scale changes in the dissolved org. C (DOC) pool and the mode of equilibration of small mols. and macromols. in the DOC pool.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaL3sXhvVGitbs%253D&md5=86b4e8fb10baed552744a1caf092bda9
  28. 28
    Harke, M. J.; Berry, D. L.; Ammerman, J. W.; Gobler, C. J. Molecular response of the bloom-forming cyanobacterium, Microcystis aeruginosa, to phosphorus limitation Microb. Ecol. 2012, 63, 188– 198 DOI: 10.1007/s00248-011-9894-8
    Google Scholar
    28
    Molecular Response of the Bloom-Forming Cyanobacterium, Microcystis aeruginosa, to Phosphorus Limitation
    Harke, Matthew J.; Berry, Dianna L.; Ammerman, James W.; Gobler, Christopher J.
    Microbial Ecology (2012), 63 (1), 188-198CODEN: MCBEBU; ISSN:0095-3628. (Springer)
    Cyanobacteria blooms caused by species such as Microcystis have become commonplace in many freshwater ecosystems. Although phosphorus (P) typically limits the growth of freshwater phytoplankton populations, little is known regarding the mol. response of Microcystis to variation in P concns. and sources. For this study, the authors examd. genes involved in P acquisition in Microcystis including two high-affinity phosphate-binding proteins (pstS and sphX) and a putative alk. phosphatase (phoX). Sequence analyses among ten clones of Microcystis aeruginosa and one clone of Microcystis wesenbergii indicates that these genes are present and conserved within the species, but perhaps not the genus, as phoX was not identified in M. wesenbergii. Expts. with clones of M. aeruginosa indicated that expression of these three genes was strongly upregulated (50- to 400-fold) under low inorg. P conditions and that the expression of phoX was correlated with alk. phosphatase activity (p < 0.005). In contrast, cultures grown exclusively on high levels of org. phosphorus sources (AMP, β-glycerol phosphate, and d-glucose-6-phosphate) or under nitrogen-limited conditions displayed neither high levels of gene expression nor alk. phosphatase activity. Since Microcystis dominates phytoplankton assemblages in summer when levels of inorg. P (Pi) are often low and/or dominate lakes with low Pi and high org. P, our findings suggest this cyanobacterium may rely on pstS, sphX, and phoX to efficiently transport Pi and exploit org. sources of P to form blooms.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC38XmsVaksA%253D%253D&md5=61f31ddae2222cd4601c17423ec36350
  29. 29
    Fischer, W. J.; Garthwaite, I.; Miles, C. O.; Ross, K. M.; Aggen, J. B.; Chamberlin, A. R.; Towers, N. R.; Dietrich, D. R. Congener-independent immunoassay for microcystins and nodularins Environ. Sci. Technol. 2001, 35 (24) 4849– 4856 DOI: 10.1021/es011182f
    Google Scholar
    29
    Congener-Independent Immunoassay for Microcystins and Nodularins
    Fischer, Werner J.; Garthwaite, Ian; Miles, Christopher O.; Ross, Kathryn M.; Aggen, James B.; Chamberlin, A. Richard; Towers, Neale R.; Dietrich, Daniel R.
    Environmental Science and Technology (2001), 35 (24), 4849-4856CODEN: ESTHAG; ISSN:0013-936X. (American Chemical Society)
    Cyanobacteria (blue-green algae) (e.g., Microcystis and Nodularia species) capable of producing toxic peptides are found in fresh and brackish water worldwide. These toxins include the microcystin (MC) heptapeptides (>60 congeners) and the nodularin pentapeptides (∼5 congeners). Cyanobacterial cyclic peptide toxins are harmful to man, other mammals, birds, and fish. Acute exposure to high concns. of these toxins causes liver damage, while subchronic or chronic exposure may promote liver tumor formation. The detection of cyclic peptide cyanobacterial toxins in surface and drinking waters has been hampered by the low limits of detection required and by the fact that the present routine detection is restricted to a few of the congeners. The unusual β-amino acid ADDA (4E,6E-3-amino-9-methoxy-2,6,8-trimethyl-10-phenyldeca-4,6-dienoic acid) is present in most (>80%) of the known toxic penta- and heptapeptide toxin congeners. Here, we report the synthesis of two ADDA-haptens, the raising of antibodies to ADDA, and the development of a competitive indirect ELISA for the detection of microcystins and nodularins utilizing these antibodies. The assay has a limit of quantitation of 0.02-0.07 ng/mL (depending on which congeners are present), lower than the WHO-proposed guideline (1 ng/mL) for drinking water, irresp. of the sample matrix (raw water, drinking water, or pure toxin in PBS). This new ELISA is robust, can be performed without sample preconcn., detects toxins in freshwater samples at lower concns. than does the protein phosphatase inhibition assay, and shows very good cross-reactivity with all cyanobacterial cyclic peptide toxin congeners tested to date (MC-LR, -RR, -YR, -LW, -LF, 3-desmethyl-MC-LR, 3-desmethyl-MC-RR, and nodularin).
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD3MXotlWhsr4%253D&md5=f9c6c0995986f8affbe5abb2ee15f76f
  30. 30
    Watzin, M. C.; Miller, E. B.; Shambaugh, A. D.; Kreider, M. A. Application of the WHO alert level framework to cyanobacterial monitoring of Lake Champlain, Vermont Environ. Toxicol. 2006, 21, 278– 288 DOI: 10.1002/tox.20181
    Google Scholar
    There is no corresponding record for this reference.
  31. 31
    Findlay, D.; Kling, H.Protocols for Measuring Biodiversity: Phytoplankton in Freshwater; Report for the Department of Fisheries and Oceans; Freshwater Institute: Winnipeg, Manitoba, 2001.
    Google Scholar
    There is no corresponding record for this reference.
  32. 32
    Ilikchyan, I. N.; McKay, R. M. L.; Zehr, J. P.; Dyhrman, S. T.; Bullerjahn, G. S. Detection and expression of the phosphonate transporter gene phnD in marine and freshwater picocyanobacteria Environ. Microbiol. 2009, 11 (5) 1314– 1324 DOI: 10.1111/j.1462-2920.2009.01869.x
    Google Scholar
    There is no corresponding record for this reference.
  33. 33
    Kaneko, T.; Nakajima, N.; Okamoto, S.; Suzuki, I.; Tanabe, Y.; Tamaoki, M.; Nakamura, Y.; Kasai, F.; Watanabe, A.; Kawashima, K.; Kishida, Y.; Ono, A.; Shimizu, Y.; Takahashi, C.; Minami, C.; Fujishiro, T.; Kohara, M.; Katoh, M.; Nakazaki, N.; Nakayama, S.; Yamada, M.; Tabata, S.; Watanabe, M. M. Complete genomic structure of the bloom-forming toxic cyanobacterium Microcystis aeruginosa NIES-843 DNA Res. 2007, 14 (6) 247– 256 DOI: 10.1093/dnares/dsm026
    Google Scholar
    33
    Complete genomic structure of the bloom-forming toxic cyanobacterium Microcystis aeruginosa NIES-843
    Kaneko, Takakazu; Nakajima, Nobuyoshi; Okamoto, Shinobu; Suzuki, Iwane; Tanabe, Yuuhiko; Tamaoki, Masanori; Nakamura, Yasukazu; Kasai, Fumie; Watanabe, Akiko; Kawashima, Kumiko; Kishida, Yoshie; Ono, Akiko; Shimizu, Yoshimi; Takahashi, Chika; Minami, Chiharu; Fujishiro, Tsunakazu; Kohara, Mitsuyo; Katoh, Midori; Nakazaki, Naomi; Nakayama, Shinobu; Yamada, Manabu; Tabata, Satoshi; Watanabe, Makoto M.
    DNA Research (2007), 14 (6), 247-256CODEN: DARSE8; ISSN:1340-2838. (Oxford University Press)
    The nucleotide sequence of the complete genome of a cyanobacterium, Microcystis aeruginosa NIES-843, was detd. The genome of M. aeruginosa is a single, circular chromosome of 5,842,795 bp in length, with an av. GC content of 42.3%. The chromosome comprises 6312 putative protein-encoding genes, two sets of rRNA genes, 42 tRNA genes representing 41 tRNA species, and genes for tmRNA, the B subunit of RNase P, SRP RNA, and 6Sa RNA. Forty-five percent of the putative protein-encoding sequences showed sequence similarity to genes of known function, 32% were similar to hypothetical genes, and the remaining 23% had no apparent similarity to reported genes. A total of 688 kb of the genome, equiv. to 11.8% of the entire genome, were composed of both insertion sequences and miniature inverted-repeat transposable elements. This is indicative of a plasticity of the M. aeruginosa genome, through a mechanism that involves homologous recombination mediated by repetitive DNA elements. In addn. to known gene clusters related to the synthesis of microcystin and cyanopeptolin, novel gene clusters that may be involved in the synthesis and modification of toxic small polypeptides were identified. Compared with other cyanobacteria, a relatively small no. of genes for two component systems and a large no. of genes for restriction-modification systems were notable characteristics of the M. aeruginosa genome. The complete genome sequence and annotation are deposited in GenBank/EMBL/DDBJ under accession no. AP009552.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD1cXjsFOqs7w%253D&md5=79ee18d10bc0399806a490752ae7cb2b
  34. 34
    Li, B.; Dewey, C. N. RSEM: accurate transcript quantification from RNA-Seq data with or without a reference genome BMC Bioinf. 2011, 12 (1) 323 DOI: 10.1186/1471-2105-12-323
    Google Scholar
    34
    RSEM: accurate transcript quantification from RNA-Seq data with or without a reference genome
    Li, Bo; Dewey, Colin N.
    BMC Bioinformatics (2011), 12 (), 323CODEN: BBMIC4; ISSN:1471-2105. (BioMed Central Ltd.)
    Background: RNA-Seq is revolutionizing the way transcript abundances are measured. A key challenge in transcript quantification from RNA-Seq data is the handling of reads that map to multiple genes or isoforms. This issue is particularly important for quantification with de novo transcriptome assemblies in the absence of sequenced genomes, as it is difficult to det. which transcripts are isoforms of the same gene. A second significant issue is the design of RNA-Seq expts., in terms of the no. of reads, read length, and whether reads come from one or both ends of cDNA fragments. Results: We present RSEM, an user-friendly software package for quantifying gene and isoform abundances from single-end or paired-end RNA-Seq data. RSEM outputs abundance ests., 95% credibility intervals, and visualization files and can also simulate RNA-Seq data. In contrast to other existing tools, the software does not require a ref. genome. Thus, in combination with a de novo transcriptome assembler, RSEM enables accurate transcript quantification for species without sequenced genomes. On simulated and real data sets, RSEM has superior or comparable performance to quantification methods that rely on a ref. genome. Taking advantage of RSEM's ability to effectively use ambiguously-mapping reads, we show that accurate gene-level abundance ests. are best obtained with large nos. of short single-end reads. On the other hand, ests. of the relative frequencies of isoforms within single genes may be improved through the use of paired-end reads, depending on the no. of possible splice forms for each gene. Conclusions: RSEM is an accurate and user-friendly software tool for quantifying transcript abundances from RNA-Seq data. As it does not rely on the existence of a ref. genome, it is particularly useful for quantification with de novo transcriptome assemblies. In addn., RSEM has enabled valuable guidance for cost-efficient design of quantification expts. with RNA-Seq, which is currently relatively expensive.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3MXhtFajtLvM&md5=dcaa624a30e2af4fd3d23c2a842dd7f7
  35. 35
    Langmead, B.; Salzberg, S. L. Fast gapped-read alignment with Bowtie 2 Nat. Methods 2012, 9 (4) 357– 9 DOI: 10.1038/nmeth.1923
    Google Scholar
    35
    Fast gapped-read alignment with Bowtie 2
    Langmead, Ben; Salzberg, Steven L.
    Nature Methods (2012), 9 (4_part1), 357-359CODEN: NMAEA3; ISSN:1548-7091. (Nature Publishing Group)
    As the rate of sequencing increases, greater throughput is demanded from read aligners. The full-text minute index is often used to make alignment very fast and memory-efficient, but the approach is ill-suited to finding longer, gapped alignments. Bowtie 2 combines the strengths of the full-text minute index with the flexibility and speed of hardware-accelerated dynamic programming algorithms to achieve a combination of high speed, sensitivity and accuracy.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC38Xjt1Oqt7c%253D&md5=ed24a9453e73cec26bc06ae841333e58
  36. 36
    Leng, N.; Dawson, J. A.; Thomson, J. A.; Ruotti, V.; Rissman, A. I.; Smits, B. M. G.; Haag, J. D.; Gould, M. N.; Stewart, R. M.; Kendziorski, C. EBSeq: an empirical Bayes hierarchical model for inference in RNA-seq experiments Bioinformatics 2013, 29 (16) 2073 DOI: 10.1093/bioinformatics/btt337
    Google Scholar
    There is no corresponding record for this reference.
  37. 37
    Soneson, C.; Delorenzi, M. A comparison of methods for differential expression analysis of RNA-seq data BMC Bioinf. 2013, 14, 91 DOI: 10.1186/1471-2105-14-91
    Google Scholar
    37
    A comparison of methods for differential expression analysis of RNA-seq data
    Soneson Charlotte; Delorenzi Mauro
    BMC bioinformatics (2013), 14 (), 91 ISSN:.
    BACKGROUND: Finding genes that are differentially expressed between conditions is an integral part of understanding the molecular basis of phenotypic variation. In the past decades, DNA microarrays have been used extensively to quantify the abundance of mRNA corresponding to different genes, and more recently high-throughput sequencing of cDNA (RNA-seq) has emerged as a powerful competitor. As the cost of sequencing decreases, it is conceivable that the use of RNA-seq for differential expression analysis will increase rapidly. To exploit the possibilities and address the challenges posed by this relatively new type of data, a number of software packages have been developed especially for differential expression analysis of RNA-seq data. RESULTS: We conducted an extensive comparison of eleven methods for differential expression analysis of RNA-seq data. All methods are freely available within the R framework and take as input a matrix of counts, i.e. the number of reads mapping to each genomic feature of interest in each of a number of samples. We evaluate the methods based on both simulated data and real RNA-seq data. CONCLUSIONS: Very small sample sizes, which are still common in RNA-seq experiments, impose problems for all evaluated methods and any results obtained under such conditions should be interpreted with caution. For larger sample sizes, the methods combining a variance-stabilizing transformation with the 'limma' method for differential expression analysis perform well under many different conditions, as does the nonparametric SAMseq method.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A280%3ADC%252BC3svmsVWksg%253D%253D&md5=dc807b97d180d1f535ecb5a06e841e7e
  38. 38
    Segata, N.; Waldron, L.; Ballarini, A.; Narasimhan, V.; Jousson, O.; Huttenhower, C. Megagenomic microbial community profiling using unique clade-specific marker genes Nat. Methods 2012, 9 (8) 811– 814 DOI: 10.1038/nmeth.2066
    Google Scholar
    38
    Metagenomic microbial community profiling using unique clade-specific marker genes
    Segata, Nicola; Waldron, Levi; Ballarini, Annalisa; Narasimhan, Vagheesh; Jousson, Olivier; Huttenhower, Curtis
    Nature Methods (2012), 9 (8), 811-814CODEN: NMAEA3; ISSN:1548-7091. (Nature Publishing Group)
    Metagenomic shotgun sequencing data can identify microbes populating a microbial community and their proportions, but existing taxonomic profiling methods are inefficient for increasingly large data sets. We present an approach that uses clade-specific marker genes to unambiguously assign reads to microbial clades more accurately and >50× faster than current approaches. We validated our metagenomic phylogenetic anal. tool, MetaPhlAn, on terabases of short reads and provide the largest metagenomic profiling to date of the human gut. It can be accessed at http://huttenhower.sph.harvard.edu/metaphlan/.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC38XotlCksL0%253D&md5=7b7d09f5ebb306843952b1e57e97bb6e
  39. 39
    Kelley, L.; Sternberg, M. Protein structure prediction on the web: a case study using hte Phyre server Nat. Protoc. 2009, 4 (3) 363– 371 DOI: 10.1038/nprot.2009.2
    Google Scholar
    There is no corresponding record for this reference.
  40. 40
    Wattam, A. R.; Abraham, D.; Dalay, O.; Disz, T. L.; Driscoll, T.; Gabbard, J. L.; Gillespie, J. J.; Gough, R.; Hix, D.; Kenyon, R.; Machi, D.; Mao, C.; Nordberg, E. K.; Olson, R.; Overbeek, R.; Pusch, G. D.; Shukla, M.; Schulman, J.; Stevens, R. L.; Sullivan, D. E.; Vonstein, V.; Warren, A.; Will, R.; Wilson, M. J.; Yoo, H. S.; Zhang, C.; Zhang, Y.; Sobral, B. W. PATRIC, the bacterial bioinformatics database and analysis resource Nucleic Acids Res. 2014, 42 (Database) D581– 91 DOI: 10.1093/nar/gkt1099
    Google Scholar
    There is no corresponding record for this reference.
  41. 41
    Krasikov, V.; Aguirre von Wobeser, E.; Dekker, H. L.; Huisman, J.; Matthijs, H. C. Time-series resolution of gradual nitrogen starvation and its impact on photosynthesis in the cyanobacterium Synechocystis PCC 6803 Physiol. Plant. 2012, 145 (3) 426– 39 DOI: 10.1111/j.1399-3054.2012.01585.x
    Google Scholar
    There is no corresponding record for this reference.
  42. 42
    Kamel, M.; Ragaa, R. Constitutive synthesis of urease in Aerobacter aerogenese PRL-R3. The effect of different nitrogenous compounds on its inhibition and formation Acta Biol. Med. Ger. 1973, 30 (4) 457
    Google Scholar
    42
    Constitutive synthesis of urease in Aerobacter aerogenes PRL-R3. Effect of different nitrogenous compounds on its inhibition and formation
    Kamel, M. Y.; Ragaa, R. Hamed
    Acta Biologica et Medica Germanica (1973), 30 (4), 457-66CODEN: ABMGAJ; ISSN:0001-5318.
    The constitutive nature of urease (I) (EC 3.5.1.5) in Aerobacter aerogenes cells was demonstrated. Among 9 different nitrogenous compds. tested for the specificity of I induction, only urea (II) and thiourea (III) produced a slight increase in the specific activity. Using (NH4)2SO4 grown cells, it was found that the I level in presence of II increased and then dropped more than 50% after 4 hr induction, due to the repression and product inhibition effect of NH4+ accumulation. The inhibitory effects of barbituric acid, thiobarbituric acid, diethylbarbituric acid, alloxan, orotic acid, xanthine, and III were demonstrated at concns. ranging from 10-4-10-3M. When phenylurea, allantoin, uracil, and biuret were tested at levels of 10-2M, they did not show any inhibitory effect on partially purified A. aerogenes I.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaE2cXjsV2rsw%253D%253D&md5=50929edf80db6653a775adb5f9ce983d
  43. 43
    Mobley, H. L. T.; Island, M. D.; Hausinger, R. P. Molecular biology of microbial ureases Microbiol. Rev. 1995, 59 (3) 451– 480
    Google Scholar
    43
    Molecular biology of microbial ureases
    Mobley, Harry L. T.; Island, Michael D.; Hausinger, Robert P.
    Microbiological Reviews (1995), 59 (3), 451-80CODEN: MBRED3; ISSN:0146-0749. (American Society for Microbiology)
    A review with 307 refs.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaK2MXot1Sjurk%253D&md5=d1000c73efd29f2e24d11b09f1dc1455
  44. 44
    Luque, I.; Forchhammer, K. Nitrogen assimilation and C/N balance sensing. In The Cyanobacteria: Molecular Biology, Genomics and Evolution, Herrero, A.; Flores, E., Eds. Caister Academic Press: Norfolk, UK, 2008; pp 335– 382.
    Google Scholar
    There is no corresponding record for this reference.
  45. 45
    Stein, L. Y. Microbiology: Cyanate fuels the nitrogen cycle Nature 2015, 524 (7563) 43– 4 DOI: 10.1038/nature14639
    Google Scholar
    There is no corresponding record for this reference.
  46. 46
    Horst, G. P.; Sarnelle, O.; White, J. D.; Hamilton, S. K.; Kaul, R. B.; Bressie, J. D. Nitrogen availability increases the toxin quota of a harmful cyanobacterium Water Res. 2014, 54, 188– 198 DOI: 10.1016/j.watres.2014.01.063
    Google Scholar
    There is no corresponding record for this reference.
  47. 47
    Downing, T. G.; Meyer, C.; Gehringer, M. M.; van de Venter, M. Microcystin content of Microcystis aeruginosa is modulated by nitrogen uptake rate relative to specific growth rate or carbon fixation rate Environ. Toxicol. 2005, 20 (3) 257– 262 DOI: 10.1002/tox.20106
    Google Scholar
    There is no corresponding record for this reference.
  48. 48
    Van de Waal, D. B.; Verspagen, J. M. H.; Lürling, M.; Van Donk, E.; Visser, P. M.; Huisman, J. The ecological stoichiometry of toxins produced by harmful cyanobacteria: an experimental test of the carbon-nutrient balance hypothesis Ecology Letters 2009, 12, 1326– 1335 DOI: 10.1111/j.1461-0248.2009.01383.x
    Google Scholar
    There is no corresponding record for this reference.
  49. 49
    Donald, D. B.; Bogard, M. J.; Finlay, K.; Leavitt, P. R. Comparative effects of urea, ammonium, and nitrate on phytoplankton abundance, community composition, and toxicity in hypereutrophic freshwaters Limnol. Oceanogr. 2011, 56 (6) 2161– 2175 DOI: 10.4319/lo.2011.56.6.2161
    Google Scholar
    49
    Comparative effects of urea, ammonium, and nitrate on phytoplankton abundance, community composition, and toxicity in hypereutrophic freshwaters
    Donald, Derek B.; Bogard, Matthew J.; Finlay, Kerri; Leavitt, Peter R.
    Limnology and Oceanography (2011), 56 (6), 2161-2175CODEN: LIOCAH; ISSN:0024-3590. (American Society of Limnology and Oceanography)
    Dissolved nitrogen (N) as urea ([NH2]2CO), nitrate (NO3-), and ammonium (NH4+) was added to naturally phosphorus (P)-rich lake water (up to 175 μg P L-1) to test the hypotheses that pollution of hypereutrophic lakes with N increases total algal abundance, alters community compn., and favors toxic cyanobacteria that do not fix atm. N2. Monthly expts. were conducted in triplicate in polymictic Wascana Lake, Saskatchewan, Canada, during July, August, and Sept. 2008 using large (> 3140 L) enclosures. Addn. of all forms of N added at 6 mg N L-1 increased total algal abundance (as chlorophyll a) by up to 350% relative to controls during August and Sept., when sol. reactive P (SRP) was > 50 μg P L-1 and dissolved N:P was < 20:1 by mass. In particular, NH4+ and urea favored non-heterocystous cyanobacteria and chlorophytes and NO3-, urea promoted chlorophytes, some cyanobacteria, and transient blooms of siliceous algae, whereas N2-fixing cyanobacteria and dinoflagellates exhibited little response to added N. Added N also increased microcystin prodn. by up to 13-fold in August and Sept., although the magnitude of response varied with N species and predominant algal taxon (Planktothrix agardhii, Microcystis spp.). These findings demonstrate that pollution with N intensifies eutrophication and algal toxicity in lakes with elevated concns. of SRP and low N:P, and that the magnitude of these effects depends on the chem. form, and hence source, of N.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3MXhs1yntL%252FL&md5=88f40ed75eef19cd20f4f47e5de0a6ae
  50. 50
    Finlay, K.; Patoine, A.; Donald, D. B.; Bogard, M. J.; Leavitt, P. R. Experimental evidence that pollution with urea can degrade water quality in phosphorus-rich lakes of the Northern Great Plains Limnol. Oceanogr. 2010, 55 (3) 1213– 1230 DOI: 10.4319/lo.2010.55.3.1213
    Google Scholar
    50
    Experimental evidence that pollution with urea can degrade water quality in phosphorus-rich lakes of the northern Great Plains
    Finlay, Kerri; Patoine, Alain; Donald, Derek B.; Bogard, Matthew J.; Leavitt, Peter R.
    Limnology and Oceanography (2010), 55 (3), 1213-1230CODEN: LIOCAH; ISSN:0024-3590. (American Society of Limnology and Oceanography)
    Urea is the most abundant nitrogen (N) fertilizer used on agricultural soils, yet its effects on adjacent aquatic ecosystems are largely unknown. Here 21-d, 3000-L mesocosm expts. were conducted monthly in a hypereutrophic lake during July-Sept. 2007 to quantify how addn. of urea might affect phytoplankton abundance, gross community compn., and algal toxicity in a phosphorus (P) -rich lake. Repeated measures anal. of variance demonstrated that addn. of sufficient urea to increase ratios of sol. N : P from ∼15:1 to >24:1 (by mass) also increased algal biomass (as Chlorophyll a) and microcystin concns. 200-400%, as non-N2-fixing but toxic cyanobacteria (Microcystis, Planktothrix) and less harmful chlorophytes (Micractinium, Oocystis) replaced colonial N2-fixing cyanobacteria (Anabaena, Aphanizomenon). No significant effects of urea amendment were recorded for trials in which N : P ratios were elevated at the start of the expt., or in which ambient light levels were reduced to 25 μmol quanta m-2 s-1, although preliminary evidence suggests that urea addn. stimulated growth of heterotrophic bacteria irresp. of light regime. Development of toxic non-N2-fixing cyanobacteria by N pollution of P-rich lakes is consistent with findings from whole-lake expts. and paleolimnol. studies of deep lakes, and suggests that the fertilization needed to feed 3 billion more people by 2050 may create conditions in which future water quality in P-replete regions is degraded further by urea export from farms and cities.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3cXotVWgu7s%253D&md5=aeb1ada0ba208efd23762de774a6f948
  51. 51
    Agrawal, M. K.; Bagchi, D.; Bagchi, S. N. Acute inhibition of protease and suppression of growth in zooplankter, Moina macrocopa, by Microcystis blooms collected in Central India Hydrobiologia 2001, 464 (1) 37– 44 DOI: 10.1023/A:1013946514556
    Google Scholar
    There is no corresponding record for this reference.
  52. 52
    Agrawal, M. K.; Zitt, A.; Bagchi, D.; Weckesser, J.; Bagchi, S. N.; von Elert, E. Characterization of proteases in guts of Daphnia magna and their inhibition by Microcystis aeruginosa PCC 7806 Environ. Toxicol. 2005, 20 (3) 314– 22 DOI: 10.1002/tox.20123
    Google Scholar
    There is no corresponding record for this reference.
  53. 53
    Gobler, C. J.; Davis, T. W.; Coyne, K. J.; Boyer, G. L. Interactive influences of nutrient loading, zooplankton grazing, and microcystin synthetase gene expression on cyanobacterial bloom dynamics in a eutrophic New York lake Harmful Algae 2007, 6 (1) 119– 133 DOI: 10.1016/j.hal.2006.08.003
    Google Scholar
    There is no corresponding record for this reference.
  54. 54
    Sunda, W. G.; Graneli, E.; Gobler, C. J. Positive feedback and the development and persistence of ecosystem disruptive algal blooms J. Phycol. 2006, 42 (5) 963– 974 DOI: 10.1111/j.1529-8817.2006.00261.x
    Google Scholar
    There is no corresponding record for this reference.
  55. 55
    Kromkamp, J. Formation and functional significance of storage products in cyanobacteria N. Z. J. Mar. Freshwater Res. 1987, 21 (3) 457– 465 DOI: 10.1080/00288330.1987.9516241
    Google Scholar
    55
    Formation and functional significance of storage products in cyanobacteria
    Kromkamp, Jacco
    New Zealand Journal of Marine and Freshwater Research (1987), 21 (3), 457-65CODEN: NZJMBS; ISSN:0028-8330.
    A review with 90 refs. The most common storage products of cyanobacteria are polyphosphate as a phosphorus storage compd., cyanophycin or phycobilin protein pigment as nitrogen storage products, and glycogen as a storage product of both carbon and energy. Nutrient uptake kinetics are regulated by the storage pools, and the patterns of regulation have a feedback effect on the amt. of accumulated nutrient in the cells. Besides having a storage function the nutrient storage products are likely to act as metabolic sinks during conditions of energy stress. Regulation of storage products is esp. strict in light-limited cultures. By increasing the rate of polysaccharide formation during growth with short photoperiods, cyanobacteria are able to sustain relatively high growth rates. This effect is enhanced by keeping respiratory losses very low.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaL1cXktlCqsL4%253D&md5=2c54cd6d864f6e882fd2386154e11ab0
  56. 56
    Allen, M. M. Cyanobacterial cell inclusions Annu. Rev. Microbiol. 1984, 38, 1– 25 DOI: 10.1146/annurev.mi.38.100184.000245
    Google Scholar
    56
    Cyanobacterial cell inclusions
    Allen, Mary Mennes
    Annual Review of Microbiology (1984), 38 (), 1-25CODEN: ARMIAZ; ISSN:0066-4227.
    A review with 151 refs.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaL2cXmtVOhsbY%253D&md5=97e0621b56ff7af66dce85a1d38a85ea
  57. 57
    Martin, P.; Dyhrman, S. T.; Lomas, M. W.; Poulton, N. J.; Van Mooy, B. A. Accumulation and enhanced cycling of polyphosphate by Sargasso Sea plankton in response to low phosphorus Proc. Natl. Acad. Sci. U. S. A. 2014, 111 (22) 8089– 94 DOI: 10.1073/pnas.1321719111
    Google Scholar
    57
    Accumulation and enhanced cycling of polyphosphate by Sargasso Sea plankton in response to low phosphorus
    Martin, Patrick; Dyhrman, Sonya T.; Lomas, Michael W.; Poulton, Nicole J.; Van Mooy, Benjamin A. S.
    Proceedings of the National Academy of Sciences of the United States of America (2014), 111 (22), 8089-8094CODEN: PNASA6; ISSN:0027-8424. (National Academy of Sciences)
    Phytoplankton alter their biochem. compn. according to nutrient availability, such that their bulk elemental compn. varies across oceanic provinces. However, the links between plankton biochem. compn. and variation in biogeochem. cycling of nutrients remain largely unknown. In a survey of phytoplankton P stress in the western North Atlantic, we found that phytoplankton in the P-depleted subtropical Sargasso Sea were enriched in the biochem. polyphosphate (polyP) compared with nutrient-rich temperate waters, contradicting the canonical oceanog. view of polyP as a luxury P storage mol. The enrichment in polyP coincided with enhanced alk. phosphatase activity and substitution of sulfolipids for phospholipids, which are both indicators of P stress. PolyP appeared to be liberated preferentially over bulk P from sinking particles in the Sargasso Sea, thereby retaining P in shallow waters. Thus, polyP cycling may form a feedback loop that attenuates the export of P when it becomes scarce, contributes bioavailable P for primary prodn., and supports the export of C and N via sinking particles.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2cXmslegs7o%253D&md5=6f497e0f5c1bc90ecaf2b2ba69568ee0
  58. 58
    Allen, M. M.; Hutchison, F. Nitrogen limitation and recovery in the cyanobacterium Aphanocapsa 6308 Arch. Microbiol. 1980, 128 (1) 1– 7 DOI: 10.1007/BF00422297
    Google Scholar
    There is no corresponding record for this reference.
  59. 59
    Van de Waal, D. B.; Ferreruela, G.; Tonk, L.; Van Donk, E.; Huisman, J.; Visser, P. M.; Matthijs, H. C. P. Pulsed nitrogen supply induces dynamic changes in the amino acid composition and microcystin production of the harmful cyanobacterium Planktothrix agardhii FEMS Microbiol. Ecol. 2010, 74 (2) 430– 438 DOI: 10.1111/j.1574-6941.2010.00958.x
    Google Scholar
    There is no corresponding record for this reference.
  60. 60
    Dyhrman, S. T.; Jenkins, B. D.; Rynearson, T. A.; Saito, M. A.; Mercier, M. L.; Alexander, H.; Whitney, L. P.; Drzewianowski, A.; Bulygin, V. V.; Bertrand, E. M.; Wu, Z.; Benitez-Nelson, C.; Heithoff, A. The transcriptome and proteome of the diatom Thalassiosira pseudonana reveal a diverse phosphorus stress response PLoS One 2012, 7 (3) e33768 DOI: 10.1371/journal.pone.0033768
    Google Scholar
    60
    The transcriptome and proteome of the diatom Thalassiosira pseudonana reveal a diverse phosphorus stress response
    Dyhrman, Sonya T.; Jenkins, Bethany D.; Rynearson, Tatiana A.; Saito, Mak A.; Mercier, Melissa L.; Alexander, Harriet; Whitney, LeAnn P.; Drzewianowski, Andrea; Bulygin, Vladimir V.; Bertrand, Erin M.; Wu, Zhijin; Benitez-Nelson, Claudia; Heithoff, Abigail
    PLoS One (2012), 7 (3), e33768CODEN: POLNCL; ISSN:1932-6203. (Public Library of Science)
    P P is a crit. driver of phytoplankton growth and ecosystem function in the ocean. Diatoms are an abundant class of marine phytoplankton that are responsible for significant amts. of primary prodn. With the control they exert on the oceanic carbon cycle, there have been a no. of studies focused on how diatoms respond to limiting macro and micronutrients such as iron and nitrogen. However, diatom physiol. responses to P deficiency are poorly understood. Here, the authors couple deep sequencing of transcript tags and quant. proteomics to analyze the diatom Thalassiosira pseudonana grown under P-replete and P-deficient conditions. Some 318 transcripts were differentially regulated with a false discovery rate of <0.05, and a total of 136 proteins were differentially abundant (p<0.05). Significant changes in the abundance of transcripts and proteins were obsd. and coordinated for multiple biochem. pathways, including glycolysis and translation. Patterns in transcript and protein abundance were also linked to physiol. changes in cellular P distributions, and enzyme activities. These data demonstrate that diatom P deficiency results in changes in cellular P allocation through polyphosphate prodn., increased P transport, a switch to utilization of dissolved org. P through increased prodn. of metalloenzymes, and a remodeling of the cell surface through prodn. of sulfolipids. Thus, these findings reveal that T. pseudonana has evolved a sophisticated response to P deficiency involving multiple biochem. strategies that are likely crit. to its ability to respond to variations in environmental P availability.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC38XlsFamt7Y%253D&md5=62f28dcff317f0086344bdb264dd5a91
  61. 61
    Grillo, J. F.; Gibson, J. Regulation of phosphate accumulation in the unicellular cyanobacterium Synechococcus J. Bacteriol. 1979, 140 (2) 508– 517
    Google Scholar
    61
    Regulation of phosphate accumulation in the unicellular cyanobacterium Synechococcus
    Grillo, John F.; Gibson, Jane
    Journal of Bacteriology (1979), 140 (2), 508-17CODEN: JOBAAY; ISSN:0021-9193.
    The P contents of acid-sol. pools, lipid, RNA, and acid-insol. polyphosphate were lowered in Synechococcus in proportion to the redn. in growth rate in phosphate-limited but not in NO3--limited continuous culture. P in these cell fractions was lost proportionately during progressive phosphate starvation of batch cultures. Acid-insol. polyphosphate was always present in all cultural conditions to ∼10% of total cell P and did not turn over during balanced exponential growth. Extensive polyphosphate formation occurred transiently when phosphate was given to cells which had been phosphate limited. This material was broken down after 8 h even with excess external orthophosphate, and its P was transferred into other cell fractions, notably RNA. Phosphate uptake kinetics indicated an invariant apparent Km of about 0.5 μM, but Vmax was 40-50-fold greater in cells from phosphate-limited cultures than in cells from NO3--limited or balanced batch cultures. Over 90% of the phosphate taken up within the 1st 30 s at 15° was recovered as orthophosphate. The uptake process is highly specific, since neither phosphate entry nor growth was affected by a 100-fold excess of arsenate. The activity of polyphosphate synthetase in cell exts. increased ≥20-fold during phosphate starvation or in phosphate-restricted growth, but polyphosphatase activity was little changed by different growth conditions. Apparently, derepression of the phosphate transport and polyphosphate-synthesizing systems as well as alk. phosphatase occurs in phosphate shortage, but the breakdown of polyphosphate in this organism is regulated by modulation of existing enzyme activity.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaL3cXlsVyhug%253D%253D&md5=3e583267266198c27838e3129f318fd7
  62. 62
    Aziz, R. K.; Breitbart, M.; Edwards, R. A. Transposases are the most abundant, most ubiquitous genes in nature Nucleic Acids Res. 2010, 38 (13) 4207– 17 DOI: 10.1093/nar/gkq140
    Google Scholar
    There is no corresponding record for this reference.
  63. 63
    Casacuberta, E.; González, J. The impact of transposable elements in environmental adaptation Mol. Ecol. 2013, 22 (6) 1503– 17 DOI: 10.1111/mec.12170
    Google Scholar
    63
    The impact of transposable elements in environmental adaptation
    Casacuberta, Elena; Gonzalez, Josefa
    Molecular Ecology (2013), 22 (6), 1503-1517CODEN: MOECEO; ISSN:0962-1083. (Wiley-Blackwell)
    A review. Transposable elements (TEs) play an important role in the responsive capacity of their hosts in the face of environmental challenges. The variety of mechanisms by which TEs influence the capacity of adaptation of the host is as large as the variety of TEs and host genomes. For example, TEs might directly affect the function of individual genes, provide a mechanism for rapidly acquiring new genetic material and disseminate regulatory elements that can lead to the creation of stress-inducible regulatory networks. In this review, the authors summarize recent examples that are part of an increasing body of evidence suggesting a significant role of TEs in the host response to an ever-changing environment, both in prokaryote and in eukaryote organisms. They argue that in the near future, the increasing availability of genome sequences and the development of new tools to discover and analyze TE insertions will further show the relevant role of TEs in environmental adaptation.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3sXktFSrsb4%253D&md5=3afa435779861707d3f739bab9f1e6bc
  64. 64
    Lin, S.; Haas, S.; Zemojtel, T.; Xiao, P.; Vingron, M.; Li, R. Genome-wide comparison of cyanobacterial transposable elements, potential genetic diversity indicators Gene 2011, 473 (2) 139– 49 DOI: 10.1016/j.gene.2010.11.011
    Google Scholar
    There is no corresponding record for this reference.
  65. 65
    Frangeul, L.; Quillardet, P.; Castets, A.-M.; Humbert, J.-F.; Matthijs, H. C.; Cortez, D.; Tolonen, A.; Zhang, C.-C.; Gribaldo, S.; Kehr, J.-C.; Zilliges, Y.; Ziemert, N.; Becker, S.; Talla, E.; Latifi, A.; Billault, A.; Lepelletier, A.; Dittmann, E.; Bouchier, C.; Tandeau de Marsac, N. Highly plastic genome of Microcystis aeruginosa PCC 7806, a ubiquitous toxic freshwater cyanobacterium BMC Genomics 2008, 9, 274 DOI: 10.1186/1471-2164-9-274
    Google Scholar
    There is no corresponding record for this reference.
  66. 66
    Makarova, K. S.; Wolf, Y. I.; Snir, S.; Koonin, E. V. Defense islands in bacterial and archaeal genomes and prediction of novel defense systems J. Bacteriol. 2011, 193 (21) 6039– 56 DOI: 10.1128/JB.05535-11
    Google Scholar
    66
    Defense islands in bacterial and archaeal genomes and prediction of novel defense systems
    Makarova, Kira S.; Wolf, Yuri I.; Snir, Sagi; Koonin, Eugene V.
    Journal of Bacteriology (2011), 193 (21), 6039-6056CODEN: JOBAAY; ISSN:0021-9193. (American Society for Microbiology)
    The arms race between cellular life forms and viruses is a major driving force of evolution. A substantial fraction of bacterial and archaeal genomes is dedicated to antivirus defense. We analyzed the distribution of defense genes and typical mobilome components (such as viral and transposon genes) in bacterial and archaeal genomes and demonstrated statistically significant clustering of antivirus defense systems and mobile genes and elements in genomic islands. The defense islands are enriched in putative operons and contain numerous overrepresented gene families. A detailed sequence anal. of the proteins encoded by genes in these families shows that many of them are diverged variants of known defense system components, whereas others show features, such as characteristic operonic organization, that are suggestive of novel defense systems. Thus, genomic islands provide abundant material for the exptl. study of bacterial and archaeal antivirus defense. Except for the CRISPR-Cas systems, different classes of defense systems, in particular toxin-antitoxin and restriction-modification systems, show nonrandom clustering in defense islands. It remains unclear to what extent these assocns. reflect functional cooperation between different defense systems and to what extent the islands are genomic "sinks" that accumulate diverse nonessential genes, particularly those acquired via horizontal gene transfer. The characteristics of defense islands resemble those of mobilome islands. Defense and mobilome genes are nonrandomly assocd. in islands, suggesting nonadaptive evolution of the islands via a preferential attachment-like mechanism underpinned by the addictive properties of defense systems such as toxins-antitoxins and an important role of horizontal mobility in the evolution of these islands.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3MXhsVSqs7bL&md5=07983aca761b34173388946d653855eb
  67. 67
    Kuno, S.; Yoshida, T.; Kamikawa, R.; Hosoda, N.; Sako, Y. The distribution of a phage-related insertion sequence element in the cyanobacterium, Microcystis aeruginosa Microbes and Environments 2010, 25 (4) 295– 301 DOI: 10.1264/jsme2.ME10125
    Google Scholar
    There is no corresponding record for this reference.
  68. 68
    Fuhrman, J. A. Marine viruses and their biogeochemical and ecological effects Nature 1999, 399 (6736) 541– 548 DOI: 10.1038/21119
    Google Scholar
    68
    Marine viruses and their biogeochemical and ecological effects
    Fuhrman, Jed A.
    Nature (London) (1999), 399 (6736), 541-548CODEN: NATUAS; ISSN:0028-0836. (Macmillan Magazines)
    Viruses are the most common biol. agents in the sea, typically numbering ten billion per L. They probably infect all organisms, can undergo rapid decay and replenishment, and influence many biogeochem. and ecol. processes, Including nutrient cycling, system respiration, particle size-distributions and sinking rates, bacterial and algal biodiversity and species distributions, algal bloom control, di-Me sulfide formation and genetic transfer. Newly developed fluorescence and mol. techniques leave the field poised to make significant advances towards evaluating and quantifying such effects.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaK1MXjvFeiurk%253D&md5=ecdc1c87569573c736c8d95d9fc810f2
  69. 69
    Suttle, C. A. Marine viruses--major players in the global ecosystem Nat. Rev. Microbiol. 2007, 5 (10) 801– 12 DOI: 10.1038/nrmicro1750
    Google Scholar
    69
    Marine viruses-major players in the global ecosystem
    Suttle, Curtis A.
    Nature Reviews Microbiology (2007), 5 (10), 801-812CODEN: NRMACK; ISSN:1740-1526. (Nature Publishing Group)
    A review concerning current knowledge of marine viruses, highlighting areas in which marine virol. is quickly advancing or seems to be poised for paradigm-shifting discoveries is given. Topics discussed include: abundance of marine viruses; viruses, mortality, and elemental cycling; microbial community structures; invertebrate and vertebrate viruses; marine virus diversity (metagenomic approaches to viral diversity); diversity, viruses, and r and K selection (rank-abundance curves and active populations, r and K selection in the marine milieu); and conclusions.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD2sXhtVeis7nK&md5=762cb3987680619e9e8b6d5dd721b78e
  70. 70
    Wilhelm, S. W.; Carberry, M. J.; Eldridge, M. L.; Poorvin, L.; Saxton, M. A.; Doblin, M. A. Marine and freshwater cyanophages in a Laurentian Great Lake: evidence from infectivity assays and molecular analyses of g20 genes Appl. Environ. Microbiol. 2006, 72 (7) 4957– 63 DOI: 10.1128/AEM.00349-06
    Google Scholar
    There is no corresponding record for this reference.
  71. 71
    Manage, P. M.; Kawabata, Z.; Nakano, S. Dynamics of cyanophage-like particles and algicidal bacteria causing Microcystis aeruginosa mortality Limnology 2001, 2 (2) 73– 78 DOI: 10.1007/s102010170002
    Google Scholar
    There is no corresponding record for this reference.
  72. 72
    Tucker, S.; Pollard, P. Identification of cyanophage Ma-LBP and infection of the cyanobacterium Microcystis aeruginosa from an Australian subtropical lake by the virus Appl. Environ. Microbiol. 2005, 71 (2) 629– 35 DOI: 10.1128/AEM.71.2.629-635.2005
    Google Scholar
    72
    Identification of cyanophage Ma-LBP and infection of the cyanobacterium Microcystis aeruginosa from an Australian subtropical lake by the virus
    Tucker, Stephen; Pollard, Peter
    Applied and Environmental Microbiology (2005), 71 (2), 629-635CODEN: AEMIDF; ISSN:0099-2240. (American Society for Microbiology)
    Viruses can control the structure of bacterial communities in aquatic environments. The aim of this project was to det. if cyanophages (viruses specific to cyanobacteria) could exert a controlling influence on the abundance of the potentially toxic cyanobacterium Microcystis aeruginosa (host). M. aeruginosa was isolated, cultured, and characterized from a subtropical monomictic lake-Lake Baroon, Sunshine Coast, Queensland, Australia. The viral communities in the lake were sepd. from cyanobacterial grazers by filtration and chloroform washing. The natural lake viral cocktail was incubated with the M. aeruginosa host growing under optimal light and nutrient conditions. The specific growth rate of the host was 0.023 h-1; generation time, 30.2 h. Within 6 days, the host abundance decreased by 95%. The d. of the cyanophage was pos. correlated with the rate of M. aeruginosa cell lysis (r2 = 0.95). The cyanophage replication time was 11.2 h, with an av. burst size of 28 viral particles per host cell. However, in 3 wk, the cultured host community recovered, possibly because the host developed resistance (immunity) to the cyanophage. The multiplicity of infection was detd. to be 2,890 virus-like particles/cultured host cell, using an undiluted lake viral population. Transmission electron microscopy showed that two types of virus were likely controlling the host cyanobacterial abundance. Both viruses displayed T7-like morphol. and belonged to the Podoviridiae group (short tails) of viruses that we called cyanophage Ma-LBP. In Lake Baroon, the no. of the cyanophage Ma-LBP was 5.6 × 104 cyanophage · ml-1, representing 0.23% of the natural viral population of 2.46 × 107 · ml-1. Our results showed that this cyanophage could be a major natural control mechanism of M. aeruginosa abundance in aquatic ecosystems like Lake Baroon. Future studies of potentially toxic cyanobacterial blooms need to consider factors that influence cyanophage attachment, infectivity, and lysis of their host alongside the phys. and chem. parameters that drive cyanobacterial growth and prodn.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD2MXhsVKgsrc%253D&md5=ce95b49e33ada5aac374920e0bc54ba4
  73. 73
    Kuno, S.; Yoshida, T.; Kaneko, T.; Sako, Y. Intricate interactions between the bloom-forming cyanobacterium Microcystis aeruginosa and foreign genetic elements, revealed by diversified clustered regularly interspaced short palindromic repeat (CRISPR) signatures Appl. Environ. Microbiol. 2012, 78 (15) 5353– 60 DOI: 10.1128/AEM.00626-12
    Google Scholar
    There is no corresponding record for this reference.
  74. 74
    Clasen, J. L.; Elser, J. J. The effect of host Chlorella NC64A carbon: phosphorus ratio on the production of Paramecium bursaria Chlorella Virus-1 Freshwater Biol. 2007, 52 (1) 112– 122 DOI: 10.1111/j.1365-2427.2006.01677.x
    Google Scholar
    74
    The effect of host Chlorella NC64A carbon: phosphorus ratio on the production of Paramecium bursaria Chlorella Virus-1
    Clasen, Jessica L.; Elser, James J.
    Freshwater Biology (2007), 52 (1), 112-122CODEN: FWBLAB; ISSN:0046-5070. (Blackwell Publishing Ltd.)
    We used the freshwater alga Chlorella NC64A (Division Chlorophyta) and its virus Paramecium bursaria Chlorella virus-1 (PBCV-1) as a model system to test for potential stoichiometric constraints on a virus-host interaction. Media phosphorus concns. were manipulated to create Chlorella NC64A host cells with low (91 ± 23) or high (453 ± 246) C: P ratio. In contrast, the C: P ratio of PBCV-1, calcd. from its biochem. compn., was 17: 1. Stoichiometric theory predicts that infection success and postinfection viral prodn. should be depressed in high C: P cultures due to insufficient intracellular P for prodn. of P-rich viral particles. Consistent with this hypothesis, viral prodn. was strongly affected by host C: P ratio. While host C: P ratio did not affect viral attachment or the percentage of new viral particles that were infectious, in the low C: P Chlorella NC64A treatment, nine times more viruses were produced per infected cell than in the high C: P treatment (158 ± 138 vs. 18 ± 18), indicating that the low C: P cells were higher quality for PBCV-1 proliferation. This result implies that the stoichiometric quality of algal cells can have a major effect on host-virus population dynamics.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD2sXitVegsrs%253D&md5=e9b696c7dbd01c86ce38ac15d8c182a4
  75. 75
    Schwarz, R.; Forchhammer, K. Acclimation of unicellular cyanobacteria to macronutrient deficiency: emergence of a complex network of cellular responses Microbiology 2005, 151 (8) 2503 DOI: 10.1099/mic.0.27883-0
    Google Scholar
    There is no corresponding record for this reference.
  76. 76
    Kaczmarzyk, D.; Fulda, M. Fatty acid activation in cyanobacteria mediated by acyl-acyl carrier protein synthetase enables fatty acid recycling Plant Physiol. 2010, 152 (3) 1598– 610 DOI: 10.1104/pp.109.148007
    Google Scholar
    76
    Fatty acid activation in cyanobacteria mediated by acyl-acyl carrier protein synthetase enables fatty acid recycling
    Kaczmarzyk, Danuta; Fulda, Martin
    Plant Physiology (2010), 152 (3), 1598-1610CODEN: PLPHAY; ISSN:0032-0889. (American Society of Plant Biologists)
    In cyanobacteria, fatty acids destined for lipid synthesis can be synthesized de novo, but also exogenous free fatty acids from the culture medium can be directly incorporated into lipids. Activation of exogenous fatty acids is likely required prior to their utilization. To identify the enzymic activity responsible for activation we cloned candidate genes from Synechocystis sp. PCC 6803 and Synechococcus elongatus PCC 7942 and identified the encoded proteins as acyl-acyl carrier protein synthetases (Aas). The enzymes catalyze the ATP-dependent esterification of fatty acids to the thiol of acyl carrier protein. The two protein sequences are only distantly related to known prokaryotic Aas proteins but they display strong similarity to sequences that can be found in almost all organisms that perform oxygenic photosynthesis. To investigate the biol. role of Aas activity in cyanobacteria, aas knockout mutants were generated in the background of Synechocystis sp. PCC 6803 and S. elongatus PCC 7942. The mutant strains showed two phenotypes characterized by the inability to utilize exogenous fatty acids and by the secretion of endogenous fatty acids into the culture medium. The analyses of extracellular and intracellular fatty acid profiles of aas mutant strains as well as labeling expts. indicated that the detected free fatty acids are released from membrane lipids. The data suggest a considerable turnover of lipid mols. and a role for Aas activity in recycling the released fatty acids. In this model, lipid degrdn. represents a third supply of fatty acids for lipid synthesis in cyanobacteria.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3cXmsF2ltrg%253D&md5=938bca49f80b01dbc675d3e4deb69fd9
  77. 77
    Postgate, J. R. Nitrogen Fixation. Cambridge University Press, Cambridge, U.K.; 1998, 3rd ed.
    Google Scholar
    There is no corresponding record for this reference.
  78. 78
    Moisander, P. H.; Cheshire, L. A.; Braddy, J.; Calandrino, E. S.; Hoffman, M.; Piehler, M. F.; Paerl, H. W. Facultative diazotrophy increases Cylindrospermopsis raciborskii competitiveness under fluctuating nitrogen availability FEMS Microbiol. Ecol. 2012, 79 (3) 800– 11 DOI: 10.1111/j.1574-6941.2011.01264.x
    Google Scholar
    There is no corresponding record for this reference.
  79. 79
    Granéli, E.; Turner, J. T. Ecology of Harmful Algae. Springer: Berlin Heidelberg, 2006.
    Google Scholar
    There is no corresponding record for this reference.
  80. 80
    Andersson, A.; Höglander, H.; Karlsson, C.; Huseby, S. Key role of phosphorus and nitrogen in regulating cyanobacterial community composition in the northern Baltic Sea Estuarine, Coastal Shelf Sci. 2015, 164, 161– 171 DOI: 10.1016/j.ecss.2015.07.013
    Google Scholar
    80
    Key role of phosphorus and nitrogen in regulating cyanobacterial community composition in the northern Baltic Sea
    Andersson, Agneta; Hoeglander, Helena; Karlsson, Chatarina; Huseby, Siv
    Estuarine, Coastal and Shelf Science (2015), 164 (), 161-171CODEN: ECSSD3; ISSN:0272-7714. (Elsevier Ltd.)
    Despite cyanobacteria being a key phytoplankton group in the Baltic Sea, the factors governing their community structure are still poorly understood. Here, we studied the occurrence of the orders Chroococcales, Oscillatoriales and Nostocales, and potentially explanatory variables at five locations in the northern Baltic Sea from June-Sept., 1998-2012. Cyanobacteria constituted 1-36% of the total phytoplankton biomass along the north-south gradient. In the Bothnian Bay, Chroococcales and Oscillatoriales dominated the cyanobacterial community, whereas in the Bothnian Sea and northern Baltic Proper, Nostocales was the dominant group. The dominance of Chroococcales was coupled to low salinity and low total phosphorus, whereas Oscillatoriales correlated with high total nitrogen and low salinity. Nostocales correlated to high total phosphorus, inorg. phosphorus and salinity. Chroococcales showed an increase over time in the offshore Bothnian Bay, whereas Nostocales increased in the coastal Bothnian Sea and coastal Baltic Proper. The increase of Nostocales in the coastal Bothnian Sea was explained by a rise in total phosphorus and decrease in dissolved inorg. nitrogen compared to an increase of total nitrogen and phosphorus in the coastal Baltic Proper. No significant trends were obsd. in the cyanobacterial community in the offshore Bothnian Sea and the offshore northern Baltic Proper. We concluded that Chroococcales may be a useful indicator for increased phosphorus levels in waters with low phosphorus concns., whereas Nostocales could be used as a quality indicator for increasing phosphorus concns. in waters with low inorg. N/P ratios (<20), such as in the coastal Bothnian Sea and Baltic Proper.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2MXhtlSisr3N&md5=61c044d1e41e414696213380e1979ffe
  81. 81
    Paerl, H. W.; Gardner, W. S.; McCarthy, M. J.; Peierls, B. L.; Wilhelm, S. W. Algal blooms: Noteworthy nitrogen Science 2014, 346 (6206) 175– 175 DOI: 10.1126/science.346.6206.175-a
    Google Scholar
    81
    Algal blooms: noteworthy nitrogen
    Paerl, Hans W.; Gardner, Wayne S.; McCarthy, Mark J.; Peierls, Benjamin L.; Wilheim, Steven W.
    Science (Washington, DC, United States) (2014), 346 (6206), 175CODEN: SCIEAS; ISSN:0036-8075. (American Association for the Advancement of Science)
    There is no expanded citation for this reference.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2cXhvVCgsrfL&md5=9daca74fc314e2f5c1c30f5fe55ca987

Cited By

Click to copy section linkSection link copied!

This article is cited by 118 publications.

  1. Hanyan Li, Bishav Bhattarai, Michael Barber, Ramesh Goel. Stringent Response of Cyanobacteria and Other Bacterioplankton during Different Stages of a Harmful Cyanobacterial Bloom. Environmental Science & Technology 2023, 57 (42) , 16016-16032. https://doi.org/10.1021/acs.est.3c03114
  2. Manoj Silva, John P. Baltrus, Daniel J. Burnett, Jonas Baltrusaitis. Water Adsorption on Hydroxyapatite and Struvite as a Function of Relative Humidity: Application of BET and Freundlich Adsorption Models. ACS Earth and Space Chemistry 2022, 6 (2) , 431-443. https://doi.org/10.1021/acsearthspacechem.1c00406
  3. Hanxiao Zhang, Shouliang Huo, Zhe Xiao, Zhuoshi He, Jun Yang, Kevin M. Yeager, Xiaochuang Li, Fengchang Wu. Climate and Nutrient-Driven Regime Shifts of Cyanobacterial Communities in Low-Latitude Plateau Lakes. Environmental Science & Technology 2021, 55 (5) , 3408-3418. https://doi.org/10.1021/acs.est.0c05234
  4. Manoj Silva, Karolina Barcauskaite, Donata Drapanauskaite, Huijie Tian, Tomáš Bučko, Jonas Baltrusaitis. Relative Humidity Facilitated Urea Particle Reaction with Salicylic Acid: A Combined In Situ Spectroscopy and DFT Study. ACS Earth and Space Chemistry 2020, 4 (7) , 1018-1028. https://doi.org/10.1021/acsearthspacechem.0c00051
  5. Kyunghyun Kim, Hyunsaing Mun, Hyunjoo Shin, Sanghyun Park, Chungseok Yu, Jaehak Lee, Yumi Yoon, Hyeonsu Chung, Hyeonjeong Yun, Kyunglak Lee, Geonhee Jeong, Jin-a Oh, Injung Lee, Haejin Lee, Taewoo Kang, Hui Seong Ryu, Jonghwan Park, Yuna Shin, Doughee Rhew. Nitrogen Stimulates Microcystis-Dominated Blooms More than Phosphorus in River Conditions That Favor Non-Nitrogen-Fixing Genera. Environmental Science & Technology 2020, 54 (12) , 7185-7193. https://doi.org/10.1021/acs.est.9b07528
  6. Regiane Natumi, Elisabeth M.-L. Janssen. Cyanopeptide Co-Production Dynamics beyond Mirocystins and Effects of Growth Stages and Nutrient Availability. Environmental Science & Technology 2020, 54 (10) , 6063-6072. https://doi.org/10.1021/acs.est.9b07334
  7. Xiangming Tang, Lauren E. Krausfeldt, Keqiang Shao, Gary R. LeCleir, Joshua M. A. Stough, Guang Gao, Gregory L. Boyer, Yunlin Zhang, Hans W. Paerl, Boqiang Qin, Steven W. Wilhelm. Seasonal Gene Expression and the Ecophysiological Implications of Toxic Microcystis aeruginosa Blooms in Lake Taihu. Environmental Science & Technology 2018, 52 (19) , 11049-11059. https://doi.org/10.1021/acs.est.8b01066
  8. Morgan M. Steffen, Timothy W. Davis, R. Michael L. McKay, George S. Bullerjahn, Lauren E. Krausfeldt, Joshua M.A. Stough, Michelle L. Neitzey, Naomi E. Gilbert, Gregory L. Boyer, Thomas H. Johengen, Duane C. Gossiaux, Ashley M. Burtner, Danna Palladino, Mark D. Rowe, Gregory J. Dick, Kevin A. Meyer, Shawn Levy, Braden E. Boone, Richard P. Stumpf, Timothy T. Wynne, Paul V. Zimba, Danielle Gutierrez, and Steven W. Wilhelm . Ecophysiological Examination of the Lake Erie Microcystis Bloom in 2014: Linkages between Biology and the Water Supply Shutdown of Toledo, OH. Environmental Science & Technology 2017, 51 (12) , 6745-6755. https://doi.org/10.1021/acs.est.7b00856
  9. Hans W. Paerl, J. Thad Scott, Mark J. McCarthy, Silvia E. Newell, Wayne S. Gardner, Karl E. Havens, Daniel K. Hoffman, Steven W. Wilhelm, and Wayne A. Wurtsbaugh . It Takes Two to Tango: When and Where Dual Nutrient (N & P) Reductions Are Needed to Protect Lakes and Downstream Ecosystems. Environmental Science & Technology 2016, 50 (20) , 10805-10813. https://doi.org/10.1021/acs.est.6b02575
  10. Linqi Tian, Ye Deng, Helong Jiang. Comparing the benthic nitrogenase activity and diazotrophic community assembly of three large river-connected freshwater lakes in eastern China. Journal of Environmental Sciences 2025, 150 , 134-148. https://doi.org/10.1016/j.jes.2024.01.041
  11. Kim Thien Nguyen Le, Juan Francisco Guerra Maldonado, Thanh-Luan Nguyen, Eyerusalem Goitom, Hana Trigui, Ndèye Adiara Ndiaye, Yves Terrat, B. Jesse Shapiro, Barry Husk, Arash Zamyadi, Sébastien Sauvé, Michèle Prévost, Sarah Dorner. The short-term effect of nitrogen on freshwater cyanobacteria and cyanotoxins. Frontiers in Water 2024, 6 https://doi.org/10.3389/frwa.2024.1432183
  12. Ryan D. Bergstrom, Joshua Fergen, Lucinda B. Johnson, Robert W. Sterner, John D. Lenters, Michael R. Twiss, Alan D. Steinman. Climate Change: A bibliometric study of the Great Lakes Basin. Journal of Great Lakes Research 2024, 50 (3) , 102316. https://doi.org/10.1016/j.jglr.2024.102316
  13. Taylor L. Hancock, Elizabeth K. Dahedl, Michael A. Kratz, Hidetoshi Urakawa. The synchronicity of bloom-forming cyanobacteria transcription patterns and hydrogen peroxide dynamics. Environmental Pollution 2024, 348 , 123812. https://doi.org/10.1016/j.envpol.2024.123812
  14. Hunter R. Baylous, Matthew F. Gladfelter, Malia I. Gardner, Madalynn Foley, Alan E. Wilson, Morgan M. Steffen. Indole-3-acetic acid promotes growth in bloom-forming Microcystis via an antioxidant response. Harmful Algae 2024, 133 , 102575. https://doi.org/10.1016/j.hal.2024.102575
  15. Qiong Wu, Chunyan Yu, Yanru Liu, Peng Xing, Huabing Li, Biao Li, Shiqiang Wan, Qinglong L Wu. Microcystis blooms caused the decreasing richness of and interactions between free-living microbial functional genes in Lake Taihu, China. FEMS Microbiology Ecology 2024, 100 (1) https://doi.org/10.1093/femsec/fiad166
  16. Xian Zhang, Lijun Xiao, Jiahui Liu, Qibai Tian, Jiaqi Xie. Trade-off in genome turnover events leading to adaptive evolution of Microcystis aeruginosa species complex. BMC Genomics 2023, 24 (1) https://doi.org/10.1186/s12864-023-09555-3
  17. Min-Ji Kim, Dayun Kang, GyuDae Lee, Kyeongnam Kim, Jinnam Kim, Jae-Ho Shin, Seungjun Lee. Interplays between cyanobacterial blooms and antibiotic resistance genes. Environment International 2023, 181 , 108268. https://doi.org/10.1016/j.envint.2023.108268
  18. John Gale, Carey Sweeney, Sara Paver, Maureen L. Coleman, Anne W. Thompson. Diverse and variable community structure of picophytoplankton across the Laurentian Great Lakes. Limnology and Oceanography 2023, 68 (10) , 2327-2345. https://doi.org/10.1002/lno.12422
  19. Renju Mohan, M. A. Anjaly, Lathika Cicily Thomas, K. B. Padmakumar. Occurrence and toxicity of cyanobacterium Microcystis aeruginosa in freshwater ecosystems of the Indian subcontinent: a review. Energy, Ecology and Environment 2023, 8 (4) , 332-343. https://doi.org/10.1007/s40974-023-00277-6
  20. Justin D. Chaffin, Judy A. Westrick, Laura A. Reitz, Thomas B. Bridgeman. Microcystin congeners in Lake Erie follow the seasonal pattern of nitrogen availability. Harmful Algae 2023, 127 , 102466. https://doi.org/10.1016/j.hal.2023.102466
  21. Emma T. Brentjens, Anika R. Bratt. Beneath the surface: spatial and temporal trends in water quality and its impacts on algal community composition in the Albemarle Sound, North Carolina. Aquatic Ecology 2023, 57 (2) , 243-262. https://doi.org/10.1007/s10452-023-10008-y
  22. Sadiya Awala Samuel, Mathias Ahii Chia, Waetsi Nya Yusufu, Suleiman Dauda, Wisdom Sohunago Japhet, James Dama Habila. Nitrogen forms and concentration influence the impact of titanium dioxide nanoparticles on the biomass and antioxidant enzyme activities of Microcystis aeruginosa. Archives of Microbiology 2023, 205 (5) https://doi.org/10.1007/s00203-023-03500-4
  23. Sophie Crevecoeur, Thomas A. Edge, Linet Cynthia Watson, Susan B. Watson, Charles W. Greer, Jan J. H. Ciborowski, Ngan Diep, Alice Dove, Kenneth G. Drouillard, Thijs Frenken, Robert Michael McKay, Arthur Zastepa, Jérôme Comte. Spatio-temporal connectivity of the aquatic microbiome associated with cyanobacterial blooms along a Great Lake riverine-lacustrine continuum. Frontiers in Microbiology 2023, 14 https://doi.org/10.3389/fmicb.2023.1073753
  24. Andrew J. Bramburger, Christopher T. Filstrup, Euan D. Reavie, Cody S. Sheik, Gordon Douglas Haffner, David C. Depew, John A. Downing. Paradox versus paradigm: A disconnect between understanding and management of freshwater cyanobacterial harmful algae blooms. Freshwater Biology 2023, 68 (2) , 191-201. https://doi.org/10.1111/fwb.14019
  25. Mark W. Lusty, Christopher J. Gobler. Repeated hydrogen peroxide dosing briefly reduces cyanobacterial blooms and microcystin while increasing fecal bacteria indicators in a eutrophic pond. Journal of Environmental Sciences 2023, 124 , 522-543. https://doi.org/10.1016/j.jes.2021.11.031
  26. Benjamin J. Kramer, Ronojoy Hem, Christopher J. Gobler. Elevated CO2 significantly increases N2 fixation, growth rates, and alters microcystin, anatoxin, and saxitoxin cell quotas in strains of the bloom-forming cyanobacteria, Dolichospermum. Harmful Algae 2022, 120 , 102354. https://doi.org/10.1016/j.hal.2022.102354
  27. Man Xiao, Michele A Burford, Susanna A Wood, Luis Aubriot, Bas W Ibelings, Matthew J Prentice, Elena F Galvanese, Ted D Harris, David P Hamilton. Schindler's legacy: from eutrophic lakes to the phosphorus utilization strategies of cyanobacteria. FEMS Microbiology Reviews 2022, 46 (6) https://doi.org/10.1093/femsre/fuac029
  28. Fahim Bashir, Arif Bashir, Vishnu D. Rajput, Noureddine Bouaïcha, Khalid M. Fazili, Samrat Adhikari, Yogesh Negi, Tatiana Minkina, Waleed Hassan Almalki, Bashir Ahmad Ganai. Microcystis sp. AE03 strain in Dal Lake harbors cylindrospermopsin and microcystin synthetase gene cluster. Frontiers in Sustainable Food Systems 2022, 6 https://doi.org/10.3389/fsufs.2022.1036111
  29. Kim Thien Nguyen Le, Juan Francisco Guerra Maldonado, Eyerusalem Goitom, Hana Trigui, Yves Terrat, Thanh-Luan Nguyen, Barry Husk, B. Jesse Shapiro, Sébastien Sauvé, Michèle Prévost, Sarah Dorner. Shotgun Metagenomic Sequencing to Assess Cyanobacterial Community Composition following Coagulation of Cyanobacterial Blooms. Toxins 2022, 14 (10) , 688. https://doi.org/10.3390/toxins14100688
  30. Benjamin J. Kramer, Jennifer G. Jankowiak, Deepak Nanjappa, Matthew J. Harke, Christopher J. Gobler. Nitrogen and phosphorus significantly alter growth, nitrogen fixation, anatoxin-a content, and the transcriptome of the bloom-forming cyanobacterium, Dolichospermum. Frontiers in Microbiology 2022, 13 https://doi.org/10.3389/fmicb.2022.955032
  31. Daniel K. Hoffman, Mark J. McCarthy, Ashlynn R. Boedecker, Justin A. Myers, Silvia E. Newell. The role of internal nitrogen loading in supporting non‐N ‐fixing harmful cyanobacterial blooms in the water column of a large eutrophic lake. Limnology and Oceanography 2022, 67 (9) , 2028-2041. https://doi.org/10.1002/lno.12185
  32. Lingling Wan, Chunlei Song, Yiyong Zhou, Xiuyun Cao. Cyanobacterial extracellular alkaline phosphatase: detection and ecological function. Journal of Oceanology and Limnology 2022, 40 (5) , 1840-1854. https://doi.org/10.1007/s00343-022-2112-3
  33. Limei Shi, Yuanfeng Cai, Shengling Gao, Min Zhang, Feizhou Chen, Xiaoli Shi, Yang Yu, Yaping Lu, Qinglong L. Wu. Gene expression pattern of microbes associated with large cyanobacterial colonies for a whole year in Lake Taihu. Water Research 2022, 223 , 118958. https://doi.org/10.1016/j.watres.2022.118958
  34. Kristin J. Painter, Jason J. Venkiteswaran, Dana F. Simon, Sung Vo Duy, Sébastien Sauvé, Helen M. Baulch. Early and late cyanobacterial bloomers in a shallow, eutrophic lake. Environmental Science: Processes & Impacts 2022, 24 (8) , 1212-1227. https://doi.org/10.1039/D2EM00078D
  35. Ferdi L. Hellweger, Robbie M. Martin, Falk Eigemann, Derek J. Smith, Gregory J. Dick, Steven W. Wilhelm. Models predict planned phosphorus load reduction will make Lake Erie more toxic. Science 2022, 376 (6596) , 1001-1005. https://doi.org/10.1126/science.abm6791
  36. Junmei Jia, Qiuwen Chen, Haidong Ren, Renjie Lu, Hui He, Peiwen Gu. Phytoplankton Composition and Their Related Factors in Five Different Lakes in China: Implications for Lake Management. International Journal of Environmental Research and Public Health 2022, 19 (5) , 3135. https://doi.org/10.3390/ijerph19053135
  37. Igor Ogashawara, Lin Li, Chase Howard, Gregory K. Druschel. Monitoring Phycocyanin with Landsat 8/Operational Land Imager Orange Contra-Band. Environments 2022, 9 (3) , 40. https://doi.org/10.3390/environments9030040
  38. Christopher J. Gobler, Jennifer G. Jankowiak. Dynamic Responses of Endosymbiotic Microbial Communities Within Microcystis Colonies in North American Lakes to Altered Nitrogen, Phosphorus, and Temperature Levels. Frontiers in Microbiology 2022, 12 https://doi.org/10.3389/fmicb.2021.781500
  39. Gail Krantzberg. Great Lakes Revitalization and Renewal. 2022, 423-439. https://doi.org/10.1016/B978-0-12-819166-8.00068-2
  40. Xiaomei Su, Alan D. Steinman, Yunlin Zhang, Hong Ling, Dan Wu. Significant Temporal and Spatial Variability in Nutrient Concentrations in a Chinese Eutrophic Shallow Lake and Its Major Tributaries. Water 2022, 14 (2) , 217. https://doi.org/10.3390/w14020217
  41. Alex Neumann, Ali Saber, Carlos Alberto Arnillas, Yuko Shimoda, Cindy Yang, Aisha Javed, Sophia Zamaria, Georgina Kaltenecker, Agnes Blukacz-Richards, Yerubandi R. Rao, Natalie Feisthauer, Anna Crolla, George B. Arhonditsis. Implementation of a watershed modelling framework to support adaptive management in the Canadian side of the Lake Erie basin. Ecological Informatics 2021, 66 , 101444. https://doi.org/10.1016/j.ecoinf.2021.101444
  42. Gregory J. Dick, Melissa B. Duhaime, Jacob T. Evans, Reagan M. Errera, Casey M. Godwin, Jenan J. Kharbush, Helena S. Nitschky, McKenzie A. Powers, Henry A. Vanderploeg, Kathryn C. Schmidt, Derek J. Smith, Colleen E. Yancey, Claire C. Zwiers, Vincent J. Denef. The genetic and ecophysiological diversity of Microcystis. Environmental Microbiology 2021, 23 (12) , 7278-7313. https://doi.org/10.1111/1462-2920.15615
  43. Saber Moradinejad, Hana Trigui, Juan Francisco Guerra Maldonado, B. Jesse Shapiro, Yves Terrat, Sébastien Sauvé, Nathalie Fortin, Arash Zamyadi, Sarah Dorner, Michèle Prévost. Metagenomic study to evaluate functional capacity of a cyanobacterial bloom during oxidation. Chemical Engineering Journal Advances 2021, 8 , 100151. https://doi.org/10.1016/j.ceja.2021.100151
  44. Zeshuang Wang, Siddiq Akbar, Yunfei Sun, Lei Gu, Lu Zhang, Kai Lyu, Yuan Huang, Zhou Yang. Cyanobacterial dominance and succession: Factors, mechanisms, predictions, and managements. Journal of Environmental Management 2021, 297 , 113281. https://doi.org/10.1016/j.jenvman.2021.113281
  45. Sukriye Celikkol, Nathalie Fortin, Nicolas Tromas, Herinandrianina Andriananjamanantsoa, Charles W. Greer. Bioavailable Nutrients (N and P) and Precipitation Patterns Drive Cyanobacterial Blooms in Missisquoi Bay, Lake Champlain. Microorganisms 2021, 9 (10) , 2097. https://doi.org/10.3390/microorganisms9102097
  46. Manuela Morais, Alexandra Marchã Penha, Maria Helena Novais, Leonel Landim, Sónia Silva Victória, Eduardo A. Morales, Luciana Gomes Barbosa. Some Observations on Phytoplankton Community Structure, Dynamics and Their Relationship to Water Quality in Five Santiago Island Reservoirs, Cape Verde. Water 2021, 13 (20) , 2888. https://doi.org/10.3390/w13202888
  47. Alexa K. Hoke, Guadalupe Reynoso, Morgan R. Smith, Malia I. Gardner, Dominique J. Lockwood, Naomi E. Gilbert, Steven W. Wilhelm, Isabella R. Becker, Grant J. Brennan, Katherine E. Crider, Shannon R. Farnan, Victoria Mendoza, Alison C. Poole, Zachary P. Zimmerman, Lucy K. Utz, Louie L. Wurch, Morgan M. Steffen, . Genomic signatures of Lake Erie bacteria suggest interaction in the Microcystis phycosphere. PLOS ONE 2021, 16 (9) , e0257017. https://doi.org/10.1371/journal.pone.0257017
  48. Hanxiao Zhang, Shouliang Huo, Rong Wang, Ze Xiao, Xiaochuang Li, Fengchang Wu. Hydrologic and nutrient-driven regime shifts of cyanobacterial and eukaryotic algal communities in a large shallow lake: Evidence from empirical state indicator and ecological network analyses. Science of The Total Environment 2021, 783 , 147059. https://doi.org/10.1016/j.scitotenv.2021.147059
  49. Susanna A. Wood, Jonathan Puddick, Ian Hawes, Konstanze Steiner, Daniel R. Dietrich, David P. Hamilton, . Variability in microcystin quotas during a Microcystis bloom in a eutrophic lake. PLOS ONE 2021, 16 (7) , e0254967. https://doi.org/10.1371/journal.pone.0254967
  50. Husein Almuhtaram, Arash Zamyadi, Ron Hofmann. Machine learning for anomaly detection in cyanobacterial fluorescence signals. Water Research 2021, 197 , 117073. https://doi.org/10.1016/j.watres.2021.117073
  51. Noémie Pascault, Olivier Rué, Valentin Loux, Jacques Pédron, Véronique Martin, Jennifer Tambosco, Cécile Bernard, Jean‐François Humbert, Julie Leloup. Insights into the cyanosphere: capturing the respective metabolisms of cyanobacteria and chemotrophic bacteria in natural conditions?. Environmental Microbiology Reports 2021, 13 (3) , 364-374. https://doi.org/10.1111/1758-2229.12944
  52. Hyeok Choi, Changseok Han, Maria G. Antoniou. Sustainable and green decomposition of cyanotoxins and cyanobacteria through the development of new photocatalytic materials. Current Opinion in Green and Sustainable Chemistry 2021, 28 , 100444. https://doi.org/10.1016/j.cogsc.2020.100444
  53. Emily Garner, Benjamin C. Davis, Erin Milligan, Matthew Forrest Blair, Ishi Keenum, Ayella Maile-Moskowitz, Jin Pan, Mariah Gnegy, Krista Liguori, Suraj Gupta, Aaron J. Prussin, Linsey C. Marr, Lenwood S. Heath, Peter J. Vikesland, Liqing Zhang, Amy Pruden. Next generation sequencing approaches to evaluate water and wastewater quality. Water Research 2021, 194 , 116907. https://doi.org/10.1016/j.watres.2021.116907
  54. Yoonja Kang, Matthew J. Harke, Dianna L. Berry, Jackie L. Collier, Steven W. Wilhelm, Sonya T. Dyhrman, Christopher J. Gobler. Transcriptomic Responses of Four Pelagophytes to Nutrient (N, P) and Light Stress. Frontiers in Marine Science 2021, 8 https://doi.org/10.3389/fmars.2021.636699
  55. Fernanda Brêda-Alves, Valéria de Oliveira Fernandes, Micheline Kézia Cordeiro-Araújo, Mathias Ahii Chia. The combined effect of clethodim (herbicide) and nitrogen variation on allelopathic interactions between Microcystis aeruginosa and Raphidiopsis raciborskii. Environmental Science and Pollution Research 2021, 28 (9) , 11528-11539. https://doi.org/10.1007/s11356-020-11367-x
  56. Rayane F. Vanderley, Kemal A. Ger, Vanessa Becker, Maria Gabriela T. A. Bezerra, Renata Panosso. Abiotic factors driving cyanobacterial biomass and composition under perennial bloom conditions in tropical latitudes. Hydrobiologia 2021, 848 (4) , 943-960. https://doi.org/10.1007/s10750-020-04504-7
  57. Minkyung Kim, Jaebok Lee, Dongwoo Yang, Hye Yoon Park, Woojun Park. Seasonal dynamics of the bacterial communities associated with cyanobacterial blooms in the Han River. Environmental Pollution 2020, 266 , 115198. https://doi.org/10.1016/j.envpol.2020.115198
  58. Saber Moradinejad, Hana Trigui, Juan Francisco Guerra Maldonado, Jesse Shapiro, Yves Terrat, Arash Zamyadi, Sarah Dorner, Michèle Prévost. Diversity Assessment of Toxic Cyanobacterial Blooms during Oxidation. Toxins 2020, 12 (11) , 728. https://doi.org/10.3390/toxins12110728
  59. Katelyn M. McKindles, Makayla A. Manes, Jonathan R. DeMarco, Andrew McClure, R. Michael McKay, Timothy W. Davis, George S. Bullerjahn, . Dissolved Microcystin Release Coincident with Lysis of a Bloom Dominated by Microcystis spp. in Western Lake Erie Attributed to a Novel Cyanophage. Applied and Environmental Microbiology 2020, 86 (22) https://doi.org/10.1128/AEM.01397-20
  60. Hanyan Li, Mike Barber, Jingrang Lu, Ramesh Goel. Microbial community successions and their dynamic functions during harmful cyanobacterial blooms in a freshwater lake. Water Research 2020, 185 , 116292. https://doi.org/10.1016/j.watres.2020.116292
  61. Y Jiang, Y Liu. Influence of increased nutrient supply on Microcystis aeruginosa at cellular and proteomic levels. Aquatic Microbial Ecology 2020, 85 , 47-58. https://doi.org/10.3354/ame01939
  62. Jean-Philippe Jenny, Orlane Anneville, Fabien Arnaud, Yoann Baulaz, Damien Bouffard, Isabelle Domaizon, Serghei A. Bocaniov, Nathalie Chèvre, Maria Dittrich, Jean-Marcel Dorioz, Erin S. Dunlop, Gaël Dur, Jean Guillard, Thibault Guinaldo, Stéphan Jacquet, Aurélien Jamoneau, Zobia Jawed, Erik Jeppesen, Gail Krantzberg, John Lenters, Barbara Leoni, Michel Meybeck, Veronica Nava, Tiina Nõges, Peeter Nõges, Martina Patelli, Victoria Pebbles, Marie-Elodie Perga, Serena Rasconi, Carl R. Ruetz, Lars Rudstam, Nico Salmaso, Sharma Sapna, Dietmar Straile, Olga Tammeorg, Michael R. Twiss, Donald G. Uzarski, Anne-Mari Ventelä, Warwick F. Vincent, Steven W. Wilhelm, Sten-Åke Wängberg, Gesa A. Weyhenmeyer. Scientists’ Warning to Humanity: Rapid degradation of the world’s large lakes. Journal of Great Lakes Research 2020, 46 (4) , 686-702. https://doi.org/10.1016/j.jglr.2020.05.006
  63. Huansheng Cao, Yohei Shimura, Morgan M. Steffen, Zhou Yang, Jingrang Lu, Allen Joel, Landon Jenkins, Masanobu Kawachi, Yanbin Yin, Ferran Garcia-Pichel, . The Trait Repertoire Enabling Cyanobacteria to Bloom Assessed through Comparative Genomic Complexity and Metatranscriptomics. mBio 2020, 11 (3) https://doi.org/10.1128/mBio.01155-20
  64. Xinchen He, Hua Wang, Lili Fan, Dongfang Liang, Yanhui Ao, Wei Zhuang. Quantifying physical transport and local proliferation of phytoplankton downstream of an eutrophicated lake. Journal of Hydrology 2020, 585 , 124796. https://doi.org/10.1016/j.jhydrol.2020.124796
  65. Lauren E. Krausfeldt, Abigail T. Farmer, Hector F. Castro, Gregory L. Boyer, Shawn R. Campagna, Steven W. Wilhelm. Nitrogen flux into metabolites and microcystins changes in response to different nitrogen sources in Microcystis aeruginosa NIES ‐843. Environmental Microbiology 2020, 22 (6) , 2419-2431. https://doi.org/10.1111/1462-2920.15032
  66. Jennifer G. Jankowiak, Christopher J. Gobler. The Composition and Function of Microbiomes Within Microcystis Colonies Are Significantly Different Than Native Bacterial Assemblages in Two North American Lakes. Frontiers in Microbiology 2020, 11 https://doi.org/10.3389/fmicb.2020.01016
  67. Kevin J. Erratt, Irena F. Creed, Charles G. Trick, . Differential Drawdown of Ammonium, Nitrate, and Urea by Freshwater Chlorophytes and Cyanobacteria 1. Journal of Phycology 2020, 56 (2) , 458-468. https://doi.org/10.1111/jpy.12960
  68. Anusuya Willis, Jason N. Woodhouse. Defining Cyanobacterial Species: Diversity and Description Through Genomics. Critical Reviews in Plant Sciences 2020, 39 (2) , 101-124. https://doi.org/10.1080/07352689.2020.1763541
  69. Yingying Huang, Silu Liu, Yingshi Shen, Jingjie Hong, Lin Peng, Lei Li, Ping Xu, Jun Hu, Xuechu Chen, Ilia Ostrovsky. Nitrogen availability affects the dynamics of Microcystis blooms by regulating the downward transport of biomass. Harmful Algae 2020, 93 , 101796. https://doi.org/10.1016/j.hal.2020.101796
  70. Azadeh Golshan, Craig Evans, Phillip Geary, Abigail Morrow, Marcel Maeder, Romà Tauler. Patterns of cyanobacterial abundance in a major drinking water reservoir: what 3 years of comprehensive monitoring data reveals?. Environmental Monitoring and Assessment 2020, 192 (2) https://doi.org/10.1007/s10661-020-8090-z
  71. Trinity L. Hamilton, Jessica R. Corman, Jeff R. Havig. Carbon and nitrogen recycling during cyanoHABs in dreissenid-invaded and non-invaded US midwestern lakes and reservoirs. Hydrobiologia 2020, 847 (3) , 939-965. https://doi.org/10.1007/s10750-019-04157-1
  72. . References. 2020, 833-948. https://doi.org/10.1016/B978-0-12-813255-5.00037-5
  73. Gwenn M.M. Hennon, Sonya T. Dyhrman. Progress and promise of omics for predicting the impacts of climate change on harmful algal blooms. Harmful Algae 2020, 91 , 101587. https://doi.org/10.1016/j.hal.2019.03.005
  74. Jingrang Lu, Bo Zhu, Ian Struewing, Ning Xu, Shunshan Duan. Nitrogen–phosphorus-associated metabolic activities during the development of a cyanobacterial bloom revealed by metatranscriptomics. Scientific Reports 2019, 9 (1) https://doi.org/10.1038/s41598-019-38481-2
  75. Minkyung Kim, Bora Shin, Jaebok Lee, Hye Yoon Park, Woojun Park. Culture-independent and culture-dependent analyses of the bacterial community in the phycosphere of cyanobloom-forming Microcystis aeruginosa. Scientific Reports 2019, 9 (1) https://doi.org/10.1038/s41598-019-56882-1
  76. Mohamed N. Mohamed, Christopher Wellen, Chris T. Parsons, William D. Taylor, George Arhonditsis, Krista M. Chomicki, Duncan Boyd, Paul Weidman, Scott O. C. Mundle, Philippe Van Cappellen, Andrew N. Sharpley, Douglas G. Haffner. Understanding and managing the re-eutrophication of Lake Erie: Knowledge gaps and research priorities. Freshwater Science 2019, 38 (4) , 675-691. https://doi.org/10.1086/705915
  77. Meng Zhang, Tao Lu, Hans W. Paerl, Yiling Chen, Zhenyan Zhang, Zhigao Zhou, Haifeng Qian, . Feedback Regulation between Aquatic Microorganisms and the Bloom-Forming Cyanobacterium Microcystis aeruginosa. Applied and Environmental Microbiology 2019, 85 (21) https://doi.org/10.1128/AEM.01362-19
  78. Zofia Taranu, Frances Pick, Irena Creed, Arthur Zastepa, Sue Watson. Meteorological and Nutrient Conditions Influence Microcystin Congeners in Freshwaters. Toxins 2019, 11 (11) , 620. https://doi.org/10.3390/toxins11110620
  79. Qiuwen Chen, Min Wang, Jianyun Zhang, Wenqing Shi, Arthur E. Mynett, Hanlu Yan, Liuming Hu. Physiological effects of nitrate, ammonium, and urea on the growth and microcystins contamination of Microcystis aeruginosa: Implication for nitrogen mitigation. Water Research 2019, 163 , 114890. https://doi.org/10.1016/j.watres.2019.114890
  80. G. Reynoso, M. R. Smith, C. P. Holmes, C. R. Keelan, S. E. McGrath, G. H. Alvarez, M. A. Coceano, K. A. Eldridge, H. I. Fried, N. E. Gilbert, M. T. Harris, L. R. Kohler, C. M. Modolo, E. A. Murray, S. M. Polisetti, D. J. Sales, E. S. Walsh, M. M. Steffen. Bacterial community structure and response to nitrogen amendments in Lake Shenandoah (VA, USA). Water Science and Technology 2019, 80 (4) , 675-684. https://doi.org/10.2166/wst.2019.311
  81. Zhe Li, Jianrong Ma, Jinsong Guo, Hans W. Paerl, Justin D. Brookes, Yan Xiao, Fang Fang, Wenjuan Ouyang, Lu Lunhui. Water quality trends in the Three Gorges Reservoir region before and after impoundment (1992–2016). Ecohydrology & Hydrobiology 2019, 19 (3) , 317-327. https://doi.org/10.1016/j.ecohyd.2018.08.005
  82. Naila-Yasmine Benayache, Tri Nguyen-Quang, Kateryna Hushchyna, Kayla McLellan, Fatima-Zohra Afri-Mehennaoui, Noureddine Bouaïcha. An Overview of Cyanobacteria Harmful Algal Bloom (CyanoHAB) Issues in Freshwater Ecosystems. 2019https://doi.org/10.5772/intechopen.84155
  83. Lee J. Pinnell, Jeffrey W. Turner. Shotgun Metagenomics Reveals the Benthic Microbial Community Response to Plastic and Bioplastic in a Coastal Marine Environment. Frontiers in Microbiology 2019, 10 https://doi.org/10.3389/fmicb.2019.01252
  84. Christian Burberg, Maja Ilić, Thomas Petzoldt, Eric von Elert. Nitrate determines growth and protease inhibitor content of the cyanobacterium Microcystis aeruginosa. Journal of Applied Phycology 2019, 31 (3) , 1697-1707. https://doi.org/10.1007/s10811-018-1674-0
  85. C.E. Binding, A. Zastepa, C. Zeng. The impact of phytoplankton community composition on optical properties and satellite observations of the 2017 western Lake Erie algal bloom. Journal of Great Lakes Research 2019, 45 (3) , 573-586. https://doi.org/10.1016/j.jglr.2018.11.015
  86. Jennifer Jankowiak, Theresa Hattenrath‐Lehmann, Benjamin J. Kramer, Megan Ladds, Christopher J. Gobler. Deciphering the effects of nitrogen, phosphorus, and temperature on cyanobacterial bloom intensification, diversity, and toxicity in western Lake Erie. Limnology and Oceanography 2019, 64 (3) , 1347-1370. https://doi.org/10.1002/lno.11120
  87. Yaying Li, Fuxia Pan, Huaiying Yao. Response of symbiotic and asymbiotic nitrogen-fixing microorganisms to nitrogen fertilizer application. Journal of Soils and Sediments 2019, 19 (4) , 1948-1958. https://doi.org/10.1007/s11368-018-2192-z
  88. Mark J. Rozmarynowycz, Benjamin F.N. Beall, George S. Bullerjahn, Gaston E. Small, Robert W. Sterner, Sandra S. Brovold, Nigel A. D'souza, Susan B. Watson, Robert Michael L. McKay. Transitions in microbial communities along a 1600 km freshwater trophic gradient. Journal of Great Lakes Research 2019, 45 (2) , 263-276. https://doi.org/10.1016/j.jglr.2019.01.004
  89. Louie L. Wurch, Harriet Alexander, Kyle R. Frischkorn, Sheean T. Haley, Christopher J. Gobler, Sonya T. Dyhrman. Transcriptional Shifts Highlight the Role of Nutrients in Harmful Brown Tide Dynamics. Frontiers in Microbiology 2019, 10 https://doi.org/10.3389/fmicb.2019.00136
  90. Sifeng Wu, Zhen Wu, Zhongyao Liang, Yong Liu, Yilin Wang. Denitrification and the controlling factors in Yunnan Plateau Lakes (China): Exploring the role of enhanced internal nitrogen cycling by algal blooms. Journal of Environmental Sciences 2019, 76 , 349-358. https://doi.org/10.1016/j.jes.2018.05.028
  91. Ruihua Dai, Yanping Zhou, Yanan Chen, Xufeng Zhang, Yangwei Yan, Dong An. Effects of arginine on the growth and microcystin-LR production of Microcystis aeruginosa in culture. Science of The Total Environment 2019, 651 , 706-712. https://doi.org/10.1016/j.scitotenv.2018.09.213
  92. Silvia E. Newell, Timothy W. Davis, Thomas H. Johengen, Duane Gossiaux, Ashley Burtner, Danna Palladino, Mark J. McCarthy. Reduced forms of nitrogen are a driver of non-nitrogen-fixing harmful cyanobacterial blooms and toxicity in Lake Erie. Harmful Algae 2019, 81 , 86-93. https://doi.org/10.1016/j.hal.2018.11.003
  93. Seenivasan Subbiah, Adcharee Karnjanapiboonwong, Jonathan D. Maul, Degeng Wang, Todd A. Anderson. Monitoring cyanobacterial toxins in a large reservoir: relationships with water quality parameters. PeerJ 2019, 7 , e7305. https://doi.org/10.7717/peerj.7305
  94. M.G. Antoniou, I. Boraei, M. Solakidou, Y. Deligiannakis, M. Abhishek, L.A. Lawton, C. Edwards. Enhancing photocatalytic degradation of the cyanotoxin microcystin-LR with the addition of sulfate-radical generating oxidants. Journal of Hazardous Materials 2018, 360 , 461-470. https://doi.org/10.1016/j.jhazmat.2018.07.111
  95. Justin D. Chaffin, Douglas D. Kane, Keara Stanislawczyk, Eric M. Parker. Accuracy of data buoys for measurement of cyanobacteria, chlorophyll, and turbidity in a large lake (Lake Erie, North America): implications for estimation of cyanobacterial bloom parameters from water quality sonde measurements. Environmental Science and Pollution Research 2018, 25 (25) , 25175-25189. https://doi.org/10.1007/s11356-018-2612-z
  96. Kevin J. Erratt, Irena F. Creed, Charles G. Trick. Comparative effects of ammonium, nitrate and urea on growth and photosynthetic efficiency of three bloom‐forming cyanobacteria. Freshwater Biology 2018, 63 (7) , 626-638. https://doi.org/10.1111/fwb.13099
  97. Connor B. Driscoll, Kevin A. Meyer, Sigitas Šulčius, Nathan M. Brown, Gregory J. Dick, Huansheng Cao, Giedrius Gasiūnas, Albertas Timinskas, Yanbin Yin, Zachary C. Landry, Timothy G. Otten, Timothy W. Davis, Susan B. Watson, Theo W. Dreher. A closely-related clade of globally distributed bloom-forming cyanobacteria within the Nostocales. Harmful Algae 2018, 77 , 93-107. https://doi.org/10.1016/j.hal.2018.05.009
  98. Benjamin J. Kramer, Timothy W. Davis, Kevin A. Meyer, Barry H. Rosen, Jennifer A. Goleski, Gregory J. Dick, Genesok Oh, Christopher J. Gobler, . Nitrogen limitation, toxin synthesis potential, and toxicity of cyanobacterial populations in Lake Okeechobee and the St. Lucie River Estuary, Florida, during the 2016 state of emergency event. PLOS ONE 2018, 13 (5) , e0196278. https://doi.org/10.1371/journal.pone.0196278
  99. Mathias A. Chia, Jennifer G. Jankowiak, Benjamin J. Kramer, Jennifer A. Goleski, I-Shuo Huang, Paul V. Zimba, Maria do Carmo Bittencourt-Oliveira, Christopher J. Gobler. Succession and toxicity of Microcystis and Anabaena ( Dolichospermum ) blooms are controlled by nutrient-dependent allelopathic interactions. Harmful Algae 2018, 74 , 67-77. https://doi.org/10.1016/j.hal.2018.03.002
  100. Nicolas Tromas, Zofia E. Taranu, Bryan D. Martin, Amy Willis, Nathalie Fortin, Charles W. Greer, B. Jesse Shapiro. Niche Separation Increases With Genetic Distance Among Bloom-Forming Cyanobacteria. Frontiers in Microbiology 2018, 9 https://doi.org/10.3389/fmicb.2018.00438
Load all citations
Download PDF
Open PDF
Go to Environmental Science & Technology
Get e-Alerts
Get e-Alerts

Environmental Science & Technology

Cite this: Environ. Sci. Technol. 2016, 50, 2, 604–615
Click to copy citationCitation copied!
https://doi.org/10.1021/acs.est.5b03931
Published December 10, 2015

Copyright © 2015 American Chemical Society. This publication is licensed under these Terms of Use.

Request reuse permissions

Article Views

4744

Altmetric

-

Citations

118
Learn about these metrics

Article Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.

Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.

The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated.

  • Abstract

    High Resolution Image
    Download MS PowerPoint Slide

    Figure 1

    Figure 1. Map of stations visited during September (hollow circles) and October (red circles) in the western basin of Lake Erie. Right inset displays the composite of MODIS Cyanobacterial Index image for Sept 24th, 2013 from the NOAA Experimental Lake Erie Harmful Algal Bloom Bulletin (http://www.glerl.noaa.gov/res/Centers/HABS/lake_erie_hab/lake_erie_hab.html). Black represents no cyanobacteria detected. Colored pixels indicate the presence of cyanobacteria.

    High Resolution Image
    Download MS PowerPoint Slide

    Figure 2

    Figure 2. (A) Prokaryotic community analysis via MetaPhlAn displaying the average percent transcripts during the October transect across the western basin of Lake Erie. (B) SRP concentrations at each station (station LET4 was below detection limits (0.003 μM) and (C) the log2 fold change in gene expression of genes involved in phosphate transport in Microcystis relative to station LET7. Error bars represent the standard deviation between biological replicates (n = 2). Stations are ordered from west to east as appearing in Figure 1.

    High Resolution Image
    Download MS PowerPoint Slide

    Figure 3

    Figure 3. Heat maps of secondary metabolite genes (microcystin (mcy), aeruginosin (aer), and cyanopeptolin (mcn)) expression (log2 fold change) for Microcystis and DIN concentration (μM) for each station and experimental treatment. White boxes indicate genes not displaying significant differential expression at each station relative to LET7 and under each treatment relative to the control. Blue colors correspond to a significant decrease in transcript abundance, while red colors correspond to a significant increase in transcript abundance. Stations are ordered from west to east as appearing in Figure 1. Nutrient additions experiments were conducted with water collected at station L16.

    High Resolution Image
    Download MS PowerPoint Slide

    Figure 4

    Figure 4. (A) The number of significant differentially expressed transposase genes in each transposase family and (B) the number of significant differentially expressed genes potentially involved in phage defense per station for Microcystis relative to station LET7. Blue denotes an increase in transcript abundance, and yellow denotes a decrease in transcript abundance. Stations are ordered from west to east as appearing in Figure 1.

    High Resolution Image
    Download MS PowerPoint Slide

    Figure 5

    Figure 5. (A) Microcystis cell densities, (B) bulk alkaline phosphatase activity, (C) microcystin concentrations, and (D) cyanobacterial abundances as measured with a Fluoroprobe at the time of harvest for the nutrient amendment experiments. Error bars represent the standard deviation between biological replicates (n = 2). Star indicates significant difference relative to the control treatment (A, C, and D) or +P treatment (B) (p < 0.001). Microcystins were measured as MC–LR equivalents.

    High Resolution Image
    Download MS PowerPoint Slide

    Figure 6

    Figure 6. (A) The log2 fold change in gene expression relative to the control of genes involved in phosphate transport and metabolism for Microcystis, (B) the number of significant differentially expressed transposase genes in each transposase family for the nutrient amendment experiments, and (C) the number of significant differentially expressed genes potentially involved in phage defense relative to the control for Microcystis.

    High Resolution Image
    Download MS PowerPoint Slide

  • References

    This article references 81 other publications.

    1. 1
      Mortimer, C. H. Fifty years of physical investigations and related limnological studies on Lake Erie, 1928–1977 J. Great Lakes Res. 1987, 13 (4) 407– 435 DOI: 10.1016/S0380-1330(87)71664-5
      1
      Fifty years of physical investigations and related limnological studies on Lake Erie, 1928-1977
      Mortimer, C. H.
      Journal of Great Lakes Research (1987), 13 (4), 407-35CODEN: JGLRDE; ISSN:0380-1330.
      The review with 120 refs. covers 50 yr of phys. investigations and related limnol. studies on Lake Erie from 1928 to 1977, including surface surges and seiches, seasonal progression of temp. and O stratification, coupling of thermal stratification with the distribution of O and P in bottom waters, currents with time scale of days or less, sedimentation, and sediment transport.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaL1cXhtlOns74%253D&md5=cc21aa312833e553da60d7c33fd778be
    2. 2
      Rinta-Kanto, J. M.; Ouellette, A. J. A.; Boyer, G. L.; Twiss, M. R.; Bridgeman, T. B.; Wilhelm, S. W. Quantification of toxic Microcystis spp. during the 2003 and 2004 blooms in western Lake Erie using quantitative real-time PCR Environ. Sci. Technol. 2005, 39 (11) 4198– 4205 DOI: 10.1021/es048249u
      2
      Quantification of Toxic Microcystis spp. during the 2003 and 2004 Blooms in Western Lake Erie using Quantitative Real-Time PCR
      Rinta-Kanto, J. M.; Ouellette, A. J. A.; Boyer, G. L.; Twiss, M. R.; Bridgeman, T. B.; Wilhelm, S. W.
      Environmental Science and Technology (2005), 39 (11), 4198-4205CODEN: ESTHAG; ISSN:0013-936X. (American Chemical Society)
      In August of 2003 and August of 2004, blooms of potentially toxic cyanobacteria Microcystis spp. persisted in western Lake Erie. Samples collected from the bloom were analyzed for the cyanobacterial toxin microcystin and the presence of Microcystis spp. cells. Ests. of microcystin toxicity exceeding 1 μg L-1 (microcystin-LR activity equiv.), the safety limit set by the World Health Organization, were found from the samples in both 2003 and 2004. The presence of Microcystis spp. in water samples was confirmed through std. polymerase chain reaction (PCR) using a combination of four primer sets. Quantification of Microcystis was accomplished by a real-time PCR assay utilizing specific primer-Taq-man probe sets targeted on a conserved, Microcystis-specific 16S rDNA fragment and a microcystin toxin synthetase gene mcyD. This approach allowed us to specifically study the distribution and abundance of toxic Microcystis in the lake in contrast to previous studies that have assessed Microcystis populations with less refined methods. On the basis of quantification by quant. real-time PCR anal., the total abundance of Microcystis cells in the bloom area varied from 4 × 108 to 2 × 103 cells L-1. The results of this study provide novel insight regarding the distribution and abundance of Microcystis spp. in the western basin of Lake Erie, a region plagued in recent years by large-scale (>20 km2) blooms. Our results suggest that the Maumee River and Bay may serve as a source for Microcystis to western and central Lake Erie.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD2MXjsVGgs7k%253D&md5=59ee5f109d38e7c0c06ed416e62cdd6c
    3. 3
      Bridgeman, T. B.; Chaffin, J. D.; Kane, D. D.; Conroy, J. D.; Panek, S. E.; Armenio, P. M. From River to Lake: Phosphorus partitioning and algal community compositional changes in Western Lake Erie J. Great Lakes Res. 2012, 38, 90– 97 DOI: 10.1016/j.jglr.2011.09.010
      3
      From river to lake: Phosphorus partitioning and algal community compositional changes in Western Lake Erie
      Bridgeman, Thomas B.; Chaffin, Justin D.; Kane, Douglas D.; Conroy, Joseph D.; Panek, Sarah E.; Armenio, Patricia M.
      Journal of Great Lakes Research (2012), 38 (1), 90-97CODEN: JGLRDE; ISSN:0380-1330. (Elsevier B.V.)
      The Maumee River is an important source of phosphorus (P) loading to western Lake Erie and potentially a source of Microcystis seed colonies contributing to the development of harmful algal blooms in the lake. Herein, we quantified P forms and size fractions, and phytoplankton community compn. in the river-lake coupled ecosystem before (June), during (August), and after (Sept.) a large Microcystis bloom in 2009. Addnl., we detd. the distribution and d. of a newly emergent cyanobacterium, Lyngbya wollei, near Maumee Bay to est. potential P sequestration. In June, dissolved org. phosphorus (DOP) was the most abundant P form whereas particulate P (partP) was most abundant in August and Sept. Green algae dominated in June (44% and 60% of total chlorophyll in river and lake, resp.) with substantial Microcystis (17%) present only in the river. Conversely, in August, Microcystis declined in the river (3%) but dominated (32%) the lake. Lake phytoplankton sequestered < 6% of water column P even during peak Microcystis blooms; in all lake samples < 112 μm non-algal particles dominated partP. Lyngbya d. averaged 19.4 g dry wt/m2, with av. Lyngbya P content of 15% (to 75% max.) of water column P. The presence of Microcystis in the river before appearing in the lake indicates that the river is a potential source of Microcystis seed colonies for later lake blooms, that DOP is an important component of early summer total P, and that L. wollei blooms have the potential to increase P retention in nearshore areas.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC38Xis1entLc%253D&md5=9ebad620f55d193dd6af5a6d239f5611
    4. 4
      Stumpf, R. P.; Wynne, T. T.; Baker, D. B.; Fahnenstiel, G. L. Interannual variability of cyanobacterial blooms in Lake Erie PLoS One 2012, 7 (8) e42444 DOI: 10.1371/journal.pone.0042444
      4
      Interannual variability of cyanobacterial blooms in Lake Erie
      Stumpf, Richard P.; Wynne, Timothy T.; Baker, David B.; Fahnenstiel, Gary L.
      PLoS One (2012), 7 (8), e42444CODEN: POLNCL; ISSN:1932-6203. (Public Library of Science)
      After a 20-yr absence, severe cyanobacterial blooms have returned to Lake Erie in the last decade, in spite of negligible change in the annual load of total phosphorus (TP). Medium-spectral Resoln. Imaging Spectrometer (MERIS) imagery was used to quantify intensity of the cyanobacterial bloom for each year from 2002 to 2011. The blooms peaked in August or later, yet correlate to discharge (Q) and TP loads only for March through June. The influence of the spring TP load appears to have started in the late 1990 s, after Dreissenid mussels colonized the lake, as hindcasts prior to 1998 are inconsistent with the obsd. blooms. The total spring Q or TP load appears sufficient to predict bloom magnitude, permitting a seasonal forecast prior to the start of the bloom.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC38XhtFKhtrvE&md5=cddba20afbce2a22595c46ed6c758f73
    5. 5
      Dolan, D. M.; Chapra, S. C. Great Lakes total phosphorus revisited: 1. Loading analysis and update (1994–2008) J. Great Lakes Res. 2012, 38 (4) 730– 740 DOI: 10.1016/j.jglr.2012.10.001
      5
      Great Lakes total phosphorus revisited: 1. Loading analysis and update (1994-2008)
      Dolan, David M.; Chapra, Steven C.
      Journal of Great Lakes Research (2012), 38 (4), 730-740CODEN: JGLRDE; ISSN:0380-1330. (Elsevier B.V.)
      A review. Phosphorus load ests. have been updated for all of the Great Lakes with an emphasis on lakes Superior, Michigan, Huron and Ontario for 1994-2008. Lake Erie phosphorus loads have been kept current with previous work and for completeness are reported here. A combination of modeling and data anal. is employed to evaluate whether target loads established by the Great Lakes Water Quality Agreement (GLWQA, 1978, Annex 3) have been and are currently being met. Data from federal, state, and provincial agencies were assembled and processed to yield annual ests. for all lakes and sources. A mass-balance model was used to check the consistency of loads and to est. interlake transport. The anal. suggests that the GLWQA target loads have been consistently met for the main bodies of lakes Superior, Michigan and Huron. However, exceedances still persist for Saginaw Bay. For lakes Erie and Ontario, loadings are currently estd. to be at or just under the target (with some notable exceptions). Because interannual variability is high, the target loads have not been met consistently for the lower Great Lakes. The anal. also indicates that, because of decreasing TP concns. in the lakes, interlake transport of TP has declined significantly since the mid-1970s. Thus, it is important that these changes be included in future assessments of compliance with TP load targets. Finally, detailed tables of the yearly (1994-2008) ests. are provided, as well as annual summaries by lake tributary basin (in Supplementary Information).
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC38XhslSltbfO&md5=d8032e9aa9cbd7f89577ccd7657bd592
    6. 6
      Han, H.; Allan, J. D.; Bosch, N. S. Historical pattern of phosphorus loading to Lake Erie watersheds J. Great Lakes Res. 2012, 38, 289– 298 DOI: 10.1016/j.jglr.2012.03.004
      6
      Historical pattern of phosphorus loading to Lake Erie watersheds
      Han, Haejin; Allan, J. David; Bosch, Nathan S.
      Journal of Great Lakes Research (2012), 38 (2), 289-298CODEN: JGLRDE; ISSN:0380-1330. (Elsevier B.V.)
      Phosphorus (P) applied to croplands in excess of crop requirements has resulted in large-scale accumulation of P in soils worldwide, leading to freshwater eutrophication from river runoff that may extend well into the future. However, several studies have reported declines in surplus P inputs to the land in recent decades. To quantify trends in P loading to Lake Erie (LE) watersheds, we estd. net anthropogenic phosphorus inputs (NAPI) to 18 LE watersheds for agricultural census years from 1935 to 2007. NAPI quantifies anthropogenic inputs of P from fertilizer use, atm. deposition and detergents, as well as the net exchange in P related to trade in food and feed. Over this 70-yr period, NAPI increased to peak values in the 1970s and subsequently declined in 2007 to a level last experienced in 1935. This rise and fall was the result of two trends: a dramatic increase in fertilizer use, which peaked in the 1970s and then declined to about two-thirds of max. values; and a steady increase in P exported as crops destined for animal feed and energy prodn. During 1974-2007, riverine phosphorus loads fluctuated, and were correlated with inter-annual variation in water discharge. However, riverine P export did not show consistent temporal trends, nor correlate with temporal trends in NAPI or fertilizer use. The fraction of P inputs exported by rivers appeared to increase sharply after the 1990s, but the cause is unknown. Thus ests. of phosphorus inputs to watersheds provide insight into changing source quantities but may be weak predictors of riverine export.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC38XmvFegtr4%253D&md5=73a2bb8372540a8858473097c2b4fa16
    7. 7
      Michalak, A. M.; Anderson, E. J.; Beletsky, D.; Boland, S.; Bosch, N. S.; Bridgeman, T. B.; Chaffin, J. D.; Cho, K.; Confesor, R.; Daloglu, I.; Depinto, J. V.; Evans, M. A.; Fahnenstiel, G. L.; He, L.; Ho, J. C.; Jenkins, L.; Johengen, T. H.; Kuo, K. C.; Laporte, E.; Liu, X.; McWilliams, M. R.; Moore, M. R.; Posselt, D. J.; Richards, R. P.; Scavia, D.; Steiner, A. L.; Verhamme, E.; Wright, D. M.; Zagorski, M. A. Record-setting algal bloom in Lake Erie caused by agricultural and meteorological trends consistent with expected future conditions Proc. Natl. Acad. Sci. U. S. A. 2013, 110 (16) 6448– 52 DOI: 10.1073/pnas.1216006110
      7
      Record-setting algal bloom in Lake Erie caused by agricultural and meteorological trends consistent with expected future conditions
      Michalak, Anna M.; Anderson, Eric J.; Beletsky, Dmitry; Boland, Steven; Bosch, Nathan S.; Bridgeman, Thomas B.; Chaffin, Justin D.; Cho, Kyunghwa; Confesor, Rem; Daloglu, Irem; DePinto, Joseph V.; Evans, Mary Anne; Fahnenstiel, Gary L.; He, Lingli; Ho, Jeff C.; Jenkins, Liza; Johengen, Thomas H.; Kuo, Kevin C.; LaPorte, Elizabeth; Liu Xiaojian; McWilliams, Michael R.; Moore, Michael R.; Posselt, Derek J.; Richards, R. Peter; Scavia, Donald; Steiner, Allison L.; Verhamme, Ed; Wright, David M.; Zagorski, Melissa A.
      Proceedings of the National Academy of Sciences of the United States of America (2013), 110 (16), 6448-6452, S6448/1-S6448/14CODEN: PNASA6; ISSN:0027-8424. (National Academy of Sciences)
      In 2011, Lake Erie experienced the largest harmful algal bloom in its recorded history, with a peak intensity over 3 times greater than any previously obsd. bloom. We show that long-term trends in agricultural practices are consistent with increasing P loading to the western basin of the lake, and that these trends, coupled with meteorol. conditions in spring 2011, produced record-breaking nutrient loads. An extended period of weak lake circulation then led to abnormally long residence times that incubated the bloom, and warm and quiescent conditions after bloom onset allowed algae to remain near the top of the water column and prevented flushing of nutrients from the system. We further find that all of these factors are consistent with expected future conditions. If a scientifically guided management plan to mitigate these impacts is not implemented, we can therefore expect this bloom to be a harbinger of future blooms in Lake Erie.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3sXnvVelsbo%253D&md5=56b087980adef31dfcd87aa306024d1e
    8. 8
      Murphy, T. P.; Irvine, K.; Guo, J.; Davies, J.; Murkin, H.; Charlton, M.; Watson, S. B. New microcystin concerns in the lower great lakes Water Qual. Res. J. Canada 2003, 38 (1) 127– 140
      8
      New microcystin concerns in the lower great lakes
      Murphy, Tom P.; Irvine, Kim; Guo, Jay; Davies, John; Murkin, Henry; Charlton, Murray; Watson, Susan B.
      Water Quality Research Journal of Canada (2003), 38 (1), 127-140CODEN: WQRCFA; ISSN:1201-3080. (Canadian Association on Water Quality)
      Water samples were collected in summer 2001 for microcystin anal., nutrient detn., and algal enumeration from Hamilton Harbor (Lake Ontario), Wendt Beach and Presque Isle (Lake Erie). Microcystin concns. varied largely and were present at acute toxicity levels only in some wind-concd. blue-green algae scums (>90% Microcystis, primarily M. botrys, M. viridis, and some M. wesenbergii) in Hamilton Harbor. In Hamilton Harbor, microcystin-RR was the main microcystin with microcystin-YR and -LR also present. Samples on August 17 and Sept. 7, collected during at the peak of the cyanobacterial bloom, contained 60 and 400 μg/L, resp. Several dying birds were obsd. in the Hamilton scums. Microcystin concns. at the Lake Erie sites were <1 μg/L, yet dead birds were common. The major limitation with this approach is that current anal. (ELISA and HPLC) methods cannot measure covalently-bound microcystins, the form assimilated into the food chain.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD3sXitFWntbo%253D&md5=1040da4666cb91c6ebd62154e4ddf376
    9. 9
      Gallo, A. Algae blooms making Toledo water undrinkable are thriving. Wall Street Journal, August 3, 2014.
      There is no corresponding record for this reference.
    10. 10
      Elser, J. J.; Bracken, M. E.; Cleland, E. E.; Gruner, D. S.; Harpole, W. S.; Hillebrand, H.; Ngai, J. T.; Seabloom, E. W.; Shurin, J. B.; Smith, J. E. Global analysis of nitrogen and phosphorus limitation of primary producers in freshwater, marine and terrestrial ecosystems Ecology Letters 2007, 10 (12) 1135– 42 DOI: 10.1111/j.1461-0248.2007.01113.x
      10
      Global analysis of nitrogen and phosphorus limitation of primary producers in freshwater, marine and terrestrial ecosystems
      Elser James J; Bracken Matthew E S; Cleland Elsa E; Gruner Daniel S; Harpole W Stanley; Hillebrand Helmut; Ngai Jacqueline T; Seabloom Eric W; Shurin Jonathan B; Smith Jennifer E
      Ecology letters (2007), 10 (12), 1135-42 ISSN:.
      The cycles of the key nutrient elements nitrogen (N) and phosphorus (P) have been massively altered by anthropogenic activities. Thus, it is essential to understand how photosynthetic production across diverse ecosystems is, or is not, limited by N and P. Via a large-scale meta-analysis of experimental enrichments, we show that P limitation is equally strong across these major habitats and that N and P limitation are equivalent within both terrestrial and freshwater systems. Furthermore, simultaneous N and P enrichment produces strongly positive synergistic responses in all three environments. Thus, contrary to some prevailing paradigms, freshwater, marine and terrestrial ecosystems are surprisingly similar in terms of N and P limitation.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A280%3ADC%252BD2snmtlCntA%253D%253D&md5=2cfe209973178bbd904f7c3829f18d49
    11. 11
      Schindler, D. W. Evolution of phosphorus limitation in lakes Science 1977, 195 (4275) 260– 262 DOI: 10.1126/science.195.4275.260
      11
      Evolution of phosphorus limitation in lakes
      Schindler, D. W.
      Science (Washington, DC, United States) (1977), 195 (4275), 260-2CODEN: SCIEAS; ISSN:0036-8075.
      The nutrient-control question of lakes is reexamd. Evidence for C and N as alternatives to P as limiting nutrients are considered.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaE2sXht1Kqt78%253D&md5=8b9b6be527db8f82cfe09a27eb4f9e24
    12. 12
      Steffen, M. M.; Belisle, B. S.; Watson, S. B.; Boyer, G. L.; Wilhelm, S. W. Status, causes and controls of cyanobacterial blooms in Lake Erie J. Great Lakes Res. 2014, 40 (2) 215– 225 DOI: 10.1016/j.jglr.2013.12.012
      12
      Status, causes and controls of cyanobacterial blooms in Lake Erie
      Steffen, Morgan M.; Belisle, B. Shafer; Watson, Sue B.; Boyer, Gregory L.; Wilhelm, Steven W.
      Journal of Great Lakes Research (2014), 40 (2), 215-225CODEN: JGLRDE; ISSN:0380-1330. (Elsevier B.V.)
      A review. The Laurentian Great Lakes are among the most prominent sources of fresh water in the world. Lake Erie's infamous cyanobacterial blooms have, however, threatened the health of this valuable freshwater resource for decades. Toxic blooms dominated by the cyanobacterium Microcystis aeruginosa have most recently been one of primary ecol. concerns for the lake. These toxic blooms impact the availability of potable water, as well as public health and revenues from the tourism and fishery industries. The socioeconomic effects of these blooms have spurred research efforts to pinpoint factors that drive bloom events. Despite decades of research and mitigation efforts, these blooms have expanded both in size and duration in recent years. However, through continued joint efforts between the Canadian and United States governments, scientists, and environmental managers, identification of the factors that drive bloom events is within reach. This review provides a summary of historical and contemporary research efforts in the realm of Lake Erie's harmful cyanobacterial blooms, both in terms of exptl. and management achievements and insufficiencies, as well as future directions on the horizon for the lake's research community.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2cXhtlGrurw%253D&md5=6bf5ad4454d30d67d5754d9916ae87aa
    13. 13
      Chaffin, J. D.; Bridgeman, T. B.; Bade, D. L. Nitrogen Constrains the Growth of Late Summer Cyanobacterial Blooms in Lake Erie Adv. Microbiol. 2013, 3, 16– 26 DOI: 10.4236/aim.2013.36A003
      13
      Nitrogen constrains the growth of late summer cyanobacterial blooms in Lake Erie
      Chaffin, Justin D.; Bridgeman, Thomas B.; Bade, Darren L.
      Advances in Microbiology (2013), 3 (6), 16-26CODEN: AMDIFS; ISSN:2165-3410. (Scientific Research Publishing, Inc.)
      Phosphorus (P) is generally considered to be the main limiting nutrient to freshwater phytoplankton productivity. However, recent research is drawing attention to the importance of nitrogen (N) in freshwater eutrophication and N often constrains growth of cyanobacteria in small lakes. In this study we detd. phytoplankton nutrient limitation in a large lake, Lake Erie during two growing seasons. During 2010 and 2011, nutrient enrichment bioassays (+P, +N and, +P and N) were conducted monthly from June through Sept. with water collected in Maumee Bay (site MB18) and in the center of the western basin (site WBC). Nutrient concns. were monitored every other week. At MB18, total P concn. was often >3 μmol/L and nitrate concn. decreased from >250 μmol/L in early summer to <1 μmol/L in late summer. Nitrogen and P levels were about five-fold less at WBC. Bioassays indicated that phyto-plankton nutrient limitation varied in summer, spatially, and even among phytoplankton groups. For site MB18, +P in-creased chlorophyll concn. in one of the eight bioassays, indicating that P did not typically limit prodn. For site WBC, +P increased chlorophyll concn. in six of the eight bioassays. As a result of very low ambient nitrate concn. (<5 μmol/L) in late summer, +N (without P) increased chlorophyll concn., suggesting symptoms of N-limitation. The N-fixing cyanobacterium Anabaena became dominant following N-limitation. This study high-lights the need to reduce P loading to restore water quality. Furthermore, due to low nitrate concn., the severity of the cyanobacterial blooms could be worse if not for N-limitation in western Lake Erie.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2cXltlOiu7k%253D&md5=dd8373dcd446cd4e46c312253d6530e7
    14. 14
      Davis, T. W.; Harke, M. J.; Marcoval, M. A.; Goleski, J.; Orano-Dawson, C.; Berry, D. L.; Gobler, C. J. Effects of nitrogenous compounds and phosphorus on the growth of toxic and non-toxic strains of Microcystis during cyanobacterial blooms Aquat. Microb. Ecol. 2010, 61, 149– 162 DOI: 10.3354/ame01445
      There is no corresponding record for this reference.
    15. 15
      Rinta-Kanto, J. M.; Konopko, E. A.; DeBruyn, J. M.; Bourbonniere, R. A.; Boyer, G. L.; Wilhelm, S. W. Lake Erie Microcystis: Relationship between microcystin production, dynamics of genotypes and environmental parameters in a large lake Harmful Algae 2009, 8 (5) 665– 673 DOI: 10.1016/j.hal.2008.12.004
      There is no corresponding record for this reference.
    16. 16
      Davis, T. W.; Watson, S. B.; Rozmarynowycz, M. J.; Ciborowski, J. J. H.; McKay, R. M.; Bullerjahn, G. S. Phylogenies of microcystin-producing cyanobacteria in the lower Laurentian Great Lakes suggest extensive genetic connectivity PLoS One 2014, 9 (9) e106093 DOI: 10.1371/journal.pone.0106093
      There is no corresponding record for this reference.
    17. 17
      Steffen, M. M.; Li, Z.; Effler, T. C.; Hauser, L. J.; Boyer, G. L.; Wilhelm, S. W. Comparative Metagenomics of Toxic Freshwater Cyanobacteria Bloom Communities on Two Continents PLoS One 2012, 7 (8) e44002 DOI: 10.1371/journal.pone.0044002
      17
      Comparative metagenomics of toxic freshwater Cyanobacteria bloom communities on two continents
      Steffen, Morgan M.; Li, Zhou; Effler, T. Chad; Hauser, Loren J.; Boyer, Gregory L.; Wilhelm, Steven W.
      PLoS One (2012), 7 (8), e44002CODEN: POLNCL; ISSN:1932-6203. (Public Library of Science)
      Toxic cyanobacterial blooms have persisted in freshwater systems around the world for centuries and appear to be globally increasing in frequency and severity. Toxins produced by bloom-assocd. cyanobacteria can have drastic impacts on the ecosystem and surrounding communities, and bloom biomass can disrupt aquatic food webs and act as a driver for hypoxia. Little is currently known regarding the genomic content of the Microcystis strains that form blooms or the companion heterotrophic community assocd. with bloom events. To address these issues, we examd. the bloom-assocd. microbial communities in single samples from Lake Erie (North America), Lake Tai (Taihu, China), and Grand Lakes St. Marys (OH, USA) using comparative metagenomics. Together the Cyanobacteria and Proteobacteria comprised >90% of each bloom bacterial community sample, although the dominant phylum varied between systems. Relative to the existing Microcystis aeruginosa NIES 843 genome, sequences from Lake Erie and Taihu revealed a no. of metagenomic islands that were absent in the environmental samples. Moreover, despite variation in the phylogenetic assignments of bloom-assocd. organisms, the functional potential of bloom members remained relatively const. between systems. This pattern was particularly noticeable in the genomic contribution of nitrogen assimilation genes. In Taihu, the genetic elements assocd. with the assimilation and metab. of nitrogen were predominantly assocd. with Proteobacteria, while these functions in the North American lakes were primarily contributed to by the Cyanobacteria. Our observations build on an emerging body of metagenomic surveys describing the functional potential of microbial communities as more highly conserved than that of their phylogenetic makeup within natural systems.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC38Xht12ht7jP&md5=cd12caa1688338a607fafb3d539ada4f
    18. 18
      Harke, M. J.; Gobler, C. J. Global transcriptional responses of the toxic cyanobacterium, Microcystis aeruginosa, to nitrogen stress, phosphorus stress, and growth on organic matter PLoS One 2013, 8 (7) e69834 DOI: 10.1371/journal.pone.0069834
      18
      Global transcriptional responses of the toxic cyanobacterium, Microcystis aeruginosa, to nitrogen stress, phosphorus stress, and growth on organic matter
      Harke, Matthew J.; Gobler, Christopher J.
      PLoS One (2013), 8 (7), e69834CODEN: POLNCL; ISSN:1932-6203. (Public Library of Science)
      Whole transcriptome shotgun sequencing (RNA-seq) was used to assess the transcriptomic response of the toxic cyanobacterium Microcystis aeruginosa during growth with low levels of dissolved inorg. nitrogen (low N), low levels of dissolved inorg. phosphorus (low P), and in the presence of high levels of high mol. wt. dissolved org. matter (HMWDOM). Under low N, one third of the genome was differentially expressed, with significant increases in transcripts obsd. among genes within the nir operon, urea transport genes (urtBCDE), and amino acid transporters while significant decreases in transcripts were obsd. in genes related to photosynthesis. There was also a significant decrease in the transcription of the microcystin synthetase gene set under low N and a significant decrease in microcystin content per Microcystis cell demonstrating that N supply influences cellular toxicity. Under low P, 27% of the genome was differentially expressed. The Pho regulon was induced leading to large increases in transcript levels of the alk. phosphatase phoX, the Pst transport system (pstABC), and the sphX gene, and transcripts of multiple sulfate transporter were also significantly more abundant. While the transcriptional response to growth on HMWDOM was smaller (5-22 % of genes differentially expressed), transcripts of multiple genes specifically assocd. with the transport and degrdn. of org. compds. were significantly more abundant within HMWDOM treatments and thus may be recruited by Microcystis to utilize these substrates. Collectively, these findings provide a comprehensive understanding of the nutritional physiol. of this toxic, bloom-forming cyanobacterium and the role of N in controlling microcystin synthesis.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3sXht1ersLjK&md5=ef180850728657830bcf2299973e4902
    19. 19
      Straub, C.; Quillardet, P.; Vergalli, J.; de Marsac, N. T.; Humbert, J.-F. A day in the life of Microcystis aeruginosa strain PCC 7806 as revealed by a transcriptomic analysis PLoS One 2011, 6 (1) e16208 DOI: 10.1371/journal.pone.0016208
      There is no corresponding record for this reference.
    20. 20
      Steffen, M. M.; Dearth, S. P.; Dill, B. D.; Li, Z.; Larsen, K. M.; Campagna, S. R.; Wilhelm, S. W. Nutrients drive transcriptional changes that maintain metabolic homeostasis but alter genome architecture in Microcystis ISME J. 2014, 8 (10) 2080– 92 DOI: 10.1038/ismej.2014.78
      20
      Nutrients drive transcriptional changes that maintain metabolic homeostasis but alter genome architecture in Microcystis
      Steffen, Morgan M.; Dearth, Stephen P.; Dill, Brian D.; Li, Zhou; Larsen, Kristen M.; Campagna, Shawn R.; Wilhelm, Steven W.
      ISME Journal (2014), 8 (10), 2080-2092CODEN: IJSOCF; ISSN:1751-7362. (Nature Publishing Group)
      The cyanobacterium Microcystis aeruginosa is a globally distributed bloom-forming organism that degrades freshwater systems around the world. Factors that drive its dispersion, diversification and success remain, however, poorly understood. To develop insight into cellular-level responses to nutrient drivers of eutrophication, RNA sequencing was coupled to a comprehensive metabolomics survey of M. aeruginosa sp. NIES 843 grown in various nutrient-reduced conditions. Transcriptomes were generated for cultures grown in nutrient-replete (with nitrate as the nitrogen (N) source), nitrogen-reduced (with nitrate, urea or ammonium acting as the N sources) and phosphate-reduced conditions. Extensive expression differences (up to 696 genes for urea-grown cells) relative to the control treatment were obsd., demonstrating that the chem. variant of nitrogen available to cells affected transcriptional activity. Of particular note, a high no. of transposase genes (up to 81) were significantly and reproducibly up-regulated relative to the control when grown on urea. Conversely, phosphorus (P) redn. resulted in a significant cessation in transcription of transposase genes, indicating that variation in nutrient chem. may influence transcription of transposases and may impact the highly mosaic genomic architecture of M. aeruginosa. Corresponding metabolomes showed comparably few differences between treatments, suggesting broad changes to gene transcription are required to maintain metabolic homeostasis under nutrient redn. The combined observations provide novel and extensive insight into the complex cellular interactions that take place in this important bloom-forming organism during variable nutrient conditions and highlight a potential unknown mol. mechanism that may drive Microcystis blooms and evolution.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2cXhs1Squ73I&md5=9d6dd595ea07c7f3874b1f10c9747828
    21. 21
      Beutler, M.; Wiltshire, K. H.; Meyer, B.; Moldaenke, C.; Lüring, C.; Meyerhöfer, M.; Hansen, U. P.; Dau, H. A fluorometric method for the differentiation of algal populations in vivo and in situ Photosynth. Res. 2002, 72 (1) 39– 53 DOI: 10.1023/A:1016026607048
      21
      A fluorometric method for the differentiation of algal populations in vivo and in situ
      Beutler, M.; Wiltshire, K. H.; Meyer, B.; Moldaenke, C.; Luering, C.; Meyerhoefer, M.; Hansen, U.-P.; Dau, H.
      Photosynthesis Research (2002), 72 (1), 39-53CODEN: PHRSDI; ISSN:0166-8595. (Kluwer Academic Publishers)
      Fingerprints of excitation spectra of chlorophyll (Chl) fluorescence can be used to differentiate 'spectral groups' of microalgae in vivo and in situ in, for example, vertical profiles within a few seconds. The investigated spectral groups of algae (green group, Chlorophyta; blue, Cyanobacteria; brown, Heterokontophyta, Haptophyta, Dinophyta; mixed, Cryptophyta) are each characterized by a specific compn. of photosynthetic antenna pigments and, consequently, by a specific excitation spectrum of the Chl fluorescence. Particularly relevant are Chl a, Chl c, phycocyanobilin, phycoerythrobilin, fucoxanthin and peridinin. A lab.-based instrument and a submersible instrument were constructed contg. light-emitting diodes to excite Chl fluorescence in five distinct wavelength ranges. Norm spectra were detd. for the four spectral algal groups (several species per group). Using these norm spectra and the actual five-point excitation spectrum of a water sample, a sep. est. of the resp. Chl concn. is rapidly obtained for each algal group. The results of diln. expts. are presented. In vivo and in situ measurements are compared with results obtained by HPLC anal. Depth profiles of the distribution of spectral algal groups taken over a time period of few seconds are shown. The method for algae differentiation described here opens up new research areas, monitoring and supervision tasks related to photosynthetic primary prodn. in aquatic environments.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD38XkvFejsb4%253D&md5=699e5fd2845e29c7c5abc73c49aba8e2
    22. 22
      Jones, M. N. Nitrate reduction by shaking with cadmium: Alternative to cadmium columns Water Res. 1984, 18, 643– 646 DOI: 10.1016/0043-1354(84)90215-X
      22
      Nitrate reduction by shaking with cadmium. Alternative to cadmium columns
      Jones, Martha N.
      Water Research (1984), 18 (5), 643-6CODEN: WATRAG; ISSN:0043-1354.
      In a manual method, small vol. water samples buffered at pH 8.5 are shaken for ∼90 min with spongy Cd to reduce NO3- to NO2-, which is detd. colorimetrically. Contact time between sample and Cd is more consistently controlled for simultaneous anal. of a large series of samples than in a column method and avoids progressive and unequal deterioration of Cd redn. capacity. Shaking 60-90 min completely reduced concns. of NO3- of 1-100 μM.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaL2cXhvFOmsL8%253D&md5=c8c3057b14a3b2f422eb4a3192e6e1db
    23. 23
      Parsons, T. R.; Maita, Y.; Lalli, C. M. A Manual of Chemical and Biological Methods for Seawater Analysis. Pergamon Press: Oxford, 1984.
      There is no corresponding record for this reference.
    24. 24
      Valderrama, J. C. The simultaneous analysis of total nitrogen and phosphorus in natural waters Mar. Chem. 1981, 10, 109– 122 DOI: 10.1016/0304-4203(81)90027-X
      There is no corresponding record for this reference.
    25. 25
      Simis, S. G. H.; Huot, Y.; Babin, M.; Seppälä, J.; Metsamaa, L. Optimization of variable fluorescence measurements of phytoplankton communities with cyanobacteria Photosynth. Res. 2012, 112, 13– 30 DOI: 10.1007/s11120-012-9729-6
      25
      Optimization of variable fluorescence measurements of phytoplankton communities with cyanobacteria
      Simis, Stefan G. H.; Huot, Yannick; Babin, Marcel; Seppaelae, Jukka; Metsamaa, Liisa
      Photosynthesis Research (2012), 112 (1), 13-30CODEN: PHRSDI; ISSN:0166-8595. (Springer)
      Excitation-emission fluorescence matrixes of phytoplankton communities were simulated from lab.-grown algae and cyanobacteria cultures, to define the optical configurations of theor. fluorometers that either minimize or maximize the representation of these phytoplankton groups in community variable fluorescence measurements. Excitation sources that match the photosystem II (PSII) action spectrum of cyanobacteria do not necessarily lead to equal representation of cyanobacteria in community fluorescence. In communities with an equal share of algae and cyanobacteria, inducible PSII fluorescence in algae can be retrieved from community fluorescence under blue excitation (450-470 nm) with high accuracy (R 2 = 1.00). The highest correlation between community and cyanobacterial variable fluorescence is obtained under orange-red excitation in the 590-650 nm range (R 2 = 0.54). Gaussian band decompn. reveals that in the presence of cyanobacteria, the emission detection slit must be narrow (up to 10 nm) and centered on PSII chlorophyll-a emission (~683 nm) to avoid severe dampening of the signal by weakly variable phycobilisomal fluorescence and non-variable photosystem I fluorescence. When these optimizations of the optical configuration of the fluorometer are followed, both cyanobacterial and algal cultures in nutrient replete exponential growth exhibit values of the max. quantum yield of charge sepn. in PSII in the range of 0.65-0.7.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC38XltlKjsb4%253D&md5=3c634869bd8dfb453eee20fd46d3629e
    26. 26
      Rattan, K. J. An inter-basin comparison of nutrient limitation and the irradiance response of pulse-amplitude modulated (PAM) fluorescence in Lake Erie phytoplankton Aquat. Ecol. 2014, 48 (1) 107– 125 DOI: 10.1007/s10452-014-9470-7
      26
      An inter-basin comparison of nutrient limitation and the irradiance response of pulse-amplitude modulated (PAM) fluorescence in Lake Erie phytoplankton
      Rattan, K. J.
      Aquatic Ecology (2014), 48 (1), 107-125CODEN: AQECF9; ISSN:1386-2588. (Springer)
      This research examd. the application of the max. quantum efficiency (Fv/Fm) and relative electron transport rate vs. irradiance curves (rETR) as a rapid, sensitive assessment of Lake Erie phytoplankton nutrient status. I evaluated the potential benefits of the variable fluorescence parameters by comparing these parameters with chem. and physiol. nutrient status assays. I tested the hypothesis that Fv/Fm and rETR curves could diagnose nutrient status in natural lake phytoplankton and be capable of discriminating which inorg. nutrient is limited temporally and spatially. Fv/Fm was on av. highest in the more eutrophic west basin (WB) and lowest in the more oligotrophic central basin (CB). According to the chem. and physiol. indicators, P deficiency was most severe in the CB during summer stratification and N deficiency was strongest in the WB during isothermal conditions. Like Fv/Fm, rETR at light satn. (rETRmax) and the initial slope of the rETR vs. irradiance curve (α) decreased as the severity of N and P deficiency increased. Amendment with N or P stimulated increased Fv/Fm, rETRmax, and α in N- and P-limited samples, resp., and abolished the photoinhibition apparent in rETR curves of nutrient-limited samples. These results supported the view that the N and P deficiency assays, and corresponding variations of variable fluorescence parameters, were valid indicators of widely variable N and P deficiency in the phytoplankton, and could be used to provide a promising tool in detg. phytoplankton nutrient status. Contrary to my hopes, it did not appear that rETR-irradiance curves could discriminate between N and P deficiency. Identification of the most limiting nutrient still demanded addnl. information beyond the variable fluorescence measurements.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2cXjtlCls7s%253D&md5=6642a6270e7986003d7ee8f7ca0ed443
    27. 27
      Hoppe, H. G. Significance of exoenzymatic activities in the ecology of brackish water: measurements by means of methylumbelliferyl-substrates Mar. Ecol.: Prog. Ser. 1983, 11 (3) 299– 308 DOI: 10.3354/meps011299
      27
      Significance of exoenzymatic activities in the ecology of brackish water: measurements by means of methylumbelliferyl substrates
      Hoppe, Hans Georg
      Marine Ecology: Progress Series (1983), 11 (3), 299-308CODEN: MESEDT; ISSN:0171-8630.
      The rates of hydrolysis of glucosides, protein-like compds., glucosaminides, and org. phosphorus compds., as well as hydrolyzation rates of naturally occurring substrate analogs were measured using fluorogenic methylumbelliferyl (I) compds. in 2 eutrophic Baltic Sea fjords and adjacent offshore waters. The activity of protease [9001-92-7] was dominant in all water samples. The activity of α-D-glucosidase [9033-06-1] and glucosaminidase [76199-21-8] varied significantly between fjords and offshore waters. An expt. with I compds. and radioactively labeled substrates indicated there is a discrepancy between the amt. of substrate hydrolyzed by exoenzymes and the amt. incorporated by bacteria. This suggests that there are medium-scale changes in the dissolved org. C (DOC) pool and the mode of equilibration of small mols. and macromols. in the DOC pool.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaL3sXhvVGitbs%253D&md5=86b4e8fb10baed552744a1caf092bda9
    28. 28
      Harke, M. J.; Berry, D. L.; Ammerman, J. W.; Gobler, C. J. Molecular response of the bloom-forming cyanobacterium, Microcystis aeruginosa, to phosphorus limitation Microb. Ecol. 2012, 63, 188– 198 DOI: 10.1007/s00248-011-9894-8
      28
      Molecular Response of the Bloom-Forming Cyanobacterium, Microcystis aeruginosa, to Phosphorus Limitation
      Harke, Matthew J.; Berry, Dianna L.; Ammerman, James W.; Gobler, Christopher J.
      Microbial Ecology (2012), 63 (1), 188-198CODEN: MCBEBU; ISSN:0095-3628. (Springer)
      Cyanobacteria blooms caused by species such as Microcystis have become commonplace in many freshwater ecosystems. Although phosphorus (P) typically limits the growth of freshwater phytoplankton populations, little is known regarding the mol. response of Microcystis to variation in P concns. and sources. For this study, the authors examd. genes involved in P acquisition in Microcystis including two high-affinity phosphate-binding proteins (pstS and sphX) and a putative alk. phosphatase (phoX). Sequence analyses among ten clones of Microcystis aeruginosa and one clone of Microcystis wesenbergii indicates that these genes are present and conserved within the species, but perhaps not the genus, as phoX was not identified in M. wesenbergii. Expts. with clones of M. aeruginosa indicated that expression of these three genes was strongly upregulated (50- to 400-fold) under low inorg. P conditions and that the expression of phoX was correlated with alk. phosphatase activity (p < 0.005). In contrast, cultures grown exclusively on high levels of org. phosphorus sources (AMP, β-glycerol phosphate, and d-glucose-6-phosphate) or under nitrogen-limited conditions displayed neither high levels of gene expression nor alk. phosphatase activity. Since Microcystis dominates phytoplankton assemblages in summer when levels of inorg. P (Pi) are often low and/or dominate lakes with low Pi and high org. P, our findings suggest this cyanobacterium may rely on pstS, sphX, and phoX to efficiently transport Pi and exploit org. sources of P to form blooms.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC38XmsVaksA%253D%253D&md5=61f31ddae2222cd4601c17423ec36350
    29. 29
      Fischer, W. J.; Garthwaite, I.; Miles, C. O.; Ross, K. M.; Aggen, J. B.; Chamberlin, A. R.; Towers, N. R.; Dietrich, D. R. Congener-independent immunoassay for microcystins and nodularins Environ. Sci. Technol. 2001, 35 (24) 4849– 4856 DOI: 10.1021/es011182f
      29
      Congener-Independent Immunoassay for Microcystins and Nodularins
      Fischer, Werner J.; Garthwaite, Ian; Miles, Christopher O.; Ross, Kathryn M.; Aggen, James B.; Chamberlin, A. Richard; Towers, Neale R.; Dietrich, Daniel R.
      Environmental Science and Technology (2001), 35 (24), 4849-4856CODEN: ESTHAG; ISSN:0013-936X. (American Chemical Society)
      Cyanobacteria (blue-green algae) (e.g., Microcystis and Nodularia species) capable of producing toxic peptides are found in fresh and brackish water worldwide. These toxins include the microcystin (MC) heptapeptides (>60 congeners) and the nodularin pentapeptides (∼5 congeners). Cyanobacterial cyclic peptide toxins are harmful to man, other mammals, birds, and fish. Acute exposure to high concns. of these toxins causes liver damage, while subchronic or chronic exposure may promote liver tumor formation. The detection of cyclic peptide cyanobacterial toxins in surface and drinking waters has been hampered by the low limits of detection required and by the fact that the present routine detection is restricted to a few of the congeners. The unusual β-amino acid ADDA (4E,6E-3-amino-9-methoxy-2,6,8-trimethyl-10-phenyldeca-4,6-dienoic acid) is present in most (>80%) of the known toxic penta- and heptapeptide toxin congeners. Here, we report the synthesis of two ADDA-haptens, the raising of antibodies to ADDA, and the development of a competitive indirect ELISA for the detection of microcystins and nodularins utilizing these antibodies. The assay has a limit of quantitation of 0.02-0.07 ng/mL (depending on which congeners are present), lower than the WHO-proposed guideline (1 ng/mL) for drinking water, irresp. of the sample matrix (raw water, drinking water, or pure toxin in PBS). This new ELISA is robust, can be performed without sample preconcn., detects toxins in freshwater samples at lower concns. than does the protein phosphatase inhibition assay, and shows very good cross-reactivity with all cyanobacterial cyclic peptide toxin congeners tested to date (MC-LR, -RR, -YR, -LW, -LF, 3-desmethyl-MC-LR, 3-desmethyl-MC-RR, and nodularin).
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD3MXotlWhsr4%253D&md5=f9c6c0995986f8affbe5abb2ee15f76f
    30. 30
      Watzin, M. C.; Miller, E. B.; Shambaugh, A. D.; Kreider, M. A. Application of the WHO alert level framework to cyanobacterial monitoring of Lake Champlain, Vermont Environ. Toxicol. 2006, 21, 278– 288 DOI: 10.1002/tox.20181
      There is no corresponding record for this reference.
    31. 31
      Findlay, D.; Kling, H.Protocols for Measuring Biodiversity: Phytoplankton in Freshwater; Report for the Department of Fisheries and Oceans; Freshwater Institute: Winnipeg, Manitoba, 2001.
      There is no corresponding record for this reference.
    32. 32
      Ilikchyan, I. N.; McKay, R. M. L.; Zehr, J. P.; Dyhrman, S. T.; Bullerjahn, G. S. Detection and expression of the phosphonate transporter gene phnD in marine and freshwater picocyanobacteria Environ. Microbiol. 2009, 11 (5) 1314– 1324 DOI: 10.1111/j.1462-2920.2009.01869.x
      There is no corresponding record for this reference.
    33. 33
      Kaneko, T.; Nakajima, N.; Okamoto, S.; Suzuki, I.; Tanabe, Y.; Tamaoki, M.; Nakamura, Y.; Kasai, F.; Watanabe, A.; Kawashima, K.; Kishida, Y.; Ono, A.; Shimizu, Y.; Takahashi, C.; Minami, C.; Fujishiro, T.; Kohara, M.; Katoh, M.; Nakazaki, N.; Nakayama, S.; Yamada, M.; Tabata, S.; Watanabe, M. M. Complete genomic structure of the bloom-forming toxic cyanobacterium Microcystis aeruginosa NIES-843 DNA Res. 2007, 14 (6) 247– 256 DOI: 10.1093/dnares/dsm026
      33
      Complete genomic structure of the bloom-forming toxic cyanobacterium Microcystis aeruginosa NIES-843
      Kaneko, Takakazu; Nakajima, Nobuyoshi; Okamoto, Shinobu; Suzuki, Iwane; Tanabe, Yuuhiko; Tamaoki, Masanori; Nakamura, Yasukazu; Kasai, Fumie; Watanabe, Akiko; Kawashima, Kumiko; Kishida, Yoshie; Ono, Akiko; Shimizu, Yoshimi; Takahashi, Chika; Minami, Chiharu; Fujishiro, Tsunakazu; Kohara, Mitsuyo; Katoh, Midori; Nakazaki, Naomi; Nakayama, Shinobu; Yamada, Manabu; Tabata, Satoshi; Watanabe, Makoto M.
      DNA Research (2007), 14 (6), 247-256CODEN: DARSE8; ISSN:1340-2838. (Oxford University Press)
      The nucleotide sequence of the complete genome of a cyanobacterium, Microcystis aeruginosa NIES-843, was detd. The genome of M. aeruginosa is a single, circular chromosome of 5,842,795 bp in length, with an av. GC content of 42.3%. The chromosome comprises 6312 putative protein-encoding genes, two sets of rRNA genes, 42 tRNA genes representing 41 tRNA species, and genes for tmRNA, the B subunit of RNase P, SRP RNA, and 6Sa RNA. Forty-five percent of the putative protein-encoding sequences showed sequence similarity to genes of known function, 32% were similar to hypothetical genes, and the remaining 23% had no apparent similarity to reported genes. A total of 688 kb of the genome, equiv. to 11.8% of the entire genome, were composed of both insertion sequences and miniature inverted-repeat transposable elements. This is indicative of a plasticity of the M. aeruginosa genome, through a mechanism that involves homologous recombination mediated by repetitive DNA elements. In addn. to known gene clusters related to the synthesis of microcystin and cyanopeptolin, novel gene clusters that may be involved in the synthesis and modification of toxic small polypeptides were identified. Compared with other cyanobacteria, a relatively small no. of genes for two component systems and a large no. of genes for restriction-modification systems were notable characteristics of the M. aeruginosa genome. The complete genome sequence and annotation are deposited in GenBank/EMBL/DDBJ under accession no. AP009552.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD1cXjsFOqs7w%253D&md5=79ee18d10bc0399806a490752ae7cb2b
    34. 34
      Li, B.; Dewey, C. N. RSEM: accurate transcript quantification from RNA-Seq data with or without a reference genome BMC Bioinf. 2011, 12 (1) 323 DOI: 10.1186/1471-2105-12-323
      34
      RSEM: accurate transcript quantification from RNA-Seq data with or without a reference genome
      Li, Bo; Dewey, Colin N.
      BMC Bioinformatics (2011), 12 (), 323CODEN: BBMIC4; ISSN:1471-2105. (BioMed Central Ltd.)
      Background: RNA-Seq is revolutionizing the way transcript abundances are measured. A key challenge in transcript quantification from RNA-Seq data is the handling of reads that map to multiple genes or isoforms. This issue is particularly important for quantification with de novo transcriptome assemblies in the absence of sequenced genomes, as it is difficult to det. which transcripts are isoforms of the same gene. A second significant issue is the design of RNA-Seq expts., in terms of the no. of reads, read length, and whether reads come from one or both ends of cDNA fragments. Results: We present RSEM, an user-friendly software package for quantifying gene and isoform abundances from single-end or paired-end RNA-Seq data. RSEM outputs abundance ests., 95% credibility intervals, and visualization files and can also simulate RNA-Seq data. In contrast to other existing tools, the software does not require a ref. genome. Thus, in combination with a de novo transcriptome assembler, RSEM enables accurate transcript quantification for species without sequenced genomes. On simulated and real data sets, RSEM has superior or comparable performance to quantification methods that rely on a ref. genome. Taking advantage of RSEM's ability to effectively use ambiguously-mapping reads, we show that accurate gene-level abundance ests. are best obtained with large nos. of short single-end reads. On the other hand, ests. of the relative frequencies of isoforms within single genes may be improved through the use of paired-end reads, depending on the no. of possible splice forms for each gene. Conclusions: RSEM is an accurate and user-friendly software tool for quantifying transcript abundances from RNA-Seq data. As it does not rely on the existence of a ref. genome, it is particularly useful for quantification with de novo transcriptome assemblies. In addn., RSEM has enabled valuable guidance for cost-efficient design of quantification expts. with RNA-Seq, which is currently relatively expensive.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3MXhtFajtLvM&md5=dcaa624a30e2af4fd3d23c2a842dd7f7
    35. 35
      Langmead, B.; Salzberg, S. L. Fast gapped-read alignment with Bowtie 2 Nat. Methods 2012, 9 (4) 357– 9 DOI: 10.1038/nmeth.1923
      35
      Fast gapped-read alignment with Bowtie 2
      Langmead, Ben; Salzberg, Steven L.
      Nature Methods (2012), 9 (4_part1), 357-359CODEN: NMAEA3; ISSN:1548-7091. (Nature Publishing Group)
      As the rate of sequencing increases, greater throughput is demanded from read aligners. The full-text minute index is often used to make alignment very fast and memory-efficient, but the approach is ill-suited to finding longer, gapped alignments. Bowtie 2 combines the strengths of the full-text minute index with the flexibility and speed of hardware-accelerated dynamic programming algorithms to achieve a combination of high speed, sensitivity and accuracy.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC38Xjt1Oqt7c%253D&md5=ed24a9453e73cec26bc06ae841333e58
    36. 36
      Leng, N.; Dawson, J. A.; Thomson, J. A.; Ruotti, V.; Rissman, A. I.; Smits, B. M. G.; Haag, J. D.; Gould, M. N.; Stewart, R. M.; Kendziorski, C. EBSeq: an empirical Bayes hierarchical model for inference in RNA-seq experiments Bioinformatics 2013, 29 (16) 2073 DOI: 10.1093/bioinformatics/btt337
      There is no corresponding record for this reference.
    37. 37
      Soneson, C.; Delorenzi, M. A comparison of methods for differential expression analysis of RNA-seq data BMC Bioinf. 2013, 14, 91 DOI: 10.1186/1471-2105-14-91
      37
      A comparison of methods for differential expression analysis of RNA-seq data
      Soneson Charlotte; Delorenzi Mauro
      BMC bioinformatics (2013), 14 (), 91 ISSN:.
      BACKGROUND: Finding genes that are differentially expressed between conditions is an integral part of understanding the molecular basis of phenotypic variation. In the past decades, DNA microarrays have been used extensively to quantify the abundance of mRNA corresponding to different genes, and more recently high-throughput sequencing of cDNA (RNA-seq) has emerged as a powerful competitor. As the cost of sequencing decreases, it is conceivable that the use of RNA-seq for differential expression analysis will increase rapidly. To exploit the possibilities and address the challenges posed by this relatively new type of data, a number of software packages have been developed especially for differential expression analysis of RNA-seq data. RESULTS: We conducted an extensive comparison of eleven methods for differential expression analysis of RNA-seq data. All methods are freely available within the R framework and take as input a matrix of counts, i.e. the number of reads mapping to each genomic feature of interest in each of a number of samples. We evaluate the methods based on both simulated data and real RNA-seq data. CONCLUSIONS: Very small sample sizes, which are still common in RNA-seq experiments, impose problems for all evaluated methods and any results obtained under such conditions should be interpreted with caution. For larger sample sizes, the methods combining a variance-stabilizing transformation with the 'limma' method for differential expression analysis perform well under many different conditions, as does the nonparametric SAMseq method.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A280%3ADC%252BC3svmsVWksg%253D%253D&md5=dc807b97d180d1f535ecb5a06e841e7e
    38. 38
      Segata, N.; Waldron, L.; Ballarini, A.; Narasimhan, V.; Jousson, O.; Huttenhower, C. Megagenomic microbial community profiling using unique clade-specific marker genes Nat. Methods 2012, 9 (8) 811– 814 DOI: 10.1038/nmeth.2066
      38
      Metagenomic microbial community profiling using unique clade-specific marker genes
      Segata, Nicola; Waldron, Levi; Ballarini, Annalisa; Narasimhan, Vagheesh; Jousson, Olivier; Huttenhower, Curtis
      Nature Methods (2012), 9 (8), 811-814CODEN: NMAEA3; ISSN:1548-7091. (Nature Publishing Group)
      Metagenomic shotgun sequencing data can identify microbes populating a microbial community and their proportions, but existing taxonomic profiling methods are inefficient for increasingly large data sets. We present an approach that uses clade-specific marker genes to unambiguously assign reads to microbial clades more accurately and >50× faster than current approaches. We validated our metagenomic phylogenetic anal. tool, MetaPhlAn, on terabases of short reads and provide the largest metagenomic profiling to date of the human gut. It can be accessed at http://huttenhower.sph.harvard.edu/metaphlan/.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC38XotlCksL0%253D&md5=7b7d09f5ebb306843952b1e57e97bb6e
    39. 39
      Kelley, L.; Sternberg, M. Protein structure prediction on the web: a case study using hte Phyre server Nat. Protoc. 2009, 4 (3) 363– 371 DOI: 10.1038/nprot.2009.2
      There is no corresponding record for this reference.
    40. 40
      Wattam, A. R.; Abraham, D.; Dalay, O.; Disz, T. L.; Driscoll, T.; Gabbard, J. L.; Gillespie, J. J.; Gough, R.; Hix, D.; Kenyon, R.; Machi, D.; Mao, C.; Nordberg, E. K.; Olson, R.; Overbeek, R.; Pusch, G. D.; Shukla, M.; Schulman, J.; Stevens, R. L.; Sullivan, D. E.; Vonstein, V.; Warren, A.; Will, R.; Wilson, M. J.; Yoo, H. S.; Zhang, C.; Zhang, Y.; Sobral, B. W. PATRIC, the bacterial bioinformatics database and analysis resource Nucleic Acids Res. 2014, 42 (Database) D581– 91 DOI: 10.1093/nar/gkt1099
      There is no corresponding record for this reference.
    41. 41
      Krasikov, V.; Aguirre von Wobeser, E.; Dekker, H. L.; Huisman, J.; Matthijs, H. C. Time-series resolution of gradual nitrogen starvation and its impact on photosynthesis in the cyanobacterium Synechocystis PCC 6803 Physiol. Plant. 2012, 145 (3) 426– 39 DOI: 10.1111/j.1399-3054.2012.01585.x
      There is no corresponding record for this reference.
    42. 42
      Kamel, M.; Ragaa, R. Constitutive synthesis of urease in Aerobacter aerogenese PRL-R3. The effect of different nitrogenous compounds on its inhibition and formation Acta Biol. Med. Ger. 1973, 30 (4) 457
      42
      Constitutive synthesis of urease in Aerobacter aerogenes PRL-R3. Effect of different nitrogenous compounds on its inhibition and formation
      Kamel, M. Y.; Ragaa, R. Hamed
      Acta Biologica et Medica Germanica (1973), 30 (4), 457-66CODEN: ABMGAJ; ISSN:0001-5318.
      The constitutive nature of urease (I) (EC 3.5.1.5) in Aerobacter aerogenes cells was demonstrated. Among 9 different nitrogenous compds. tested for the specificity of I induction, only urea (II) and thiourea (III) produced a slight increase in the specific activity. Using (NH4)2SO4 grown cells, it was found that the I level in presence of II increased and then dropped more than 50% after 4 hr induction, due to the repression and product inhibition effect of NH4+ accumulation. The inhibitory effects of barbituric acid, thiobarbituric acid, diethylbarbituric acid, alloxan, orotic acid, xanthine, and III were demonstrated at concns. ranging from 10-4-10-3M. When phenylurea, allantoin, uracil, and biuret were tested at levels of 10-2M, they did not show any inhibitory effect on partially purified A. aerogenes I.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaE2cXjsV2rsw%253D%253D&md5=50929edf80db6653a775adb5f9ce983d
    43. 43
      Mobley, H. L. T.; Island, M. D.; Hausinger, R. P. Molecular biology of microbial ureases Microbiol. Rev. 1995, 59 (3) 451– 480
      43
      Molecular biology of microbial ureases
      Mobley, Harry L. T.; Island, Michael D.; Hausinger, Robert P.
      Microbiological Reviews (1995), 59 (3), 451-80CODEN: MBRED3; ISSN:0146-0749. (American Society for Microbiology)
      A review with 307 refs.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaK2MXot1Sjurk%253D&md5=d1000c73efd29f2e24d11b09f1dc1455
    44. 44
      Luque, I.; Forchhammer, K. Nitrogen assimilation and C/N balance sensing. In The Cyanobacteria: Molecular Biology, Genomics and Evolution, Herrero, A.; Flores, E., Eds. Caister Academic Press: Norfolk, UK, 2008; pp 335– 382.
      There is no corresponding record for this reference.
    45. 45
      Stein, L. Y. Microbiology: Cyanate fuels the nitrogen cycle Nature 2015, 524 (7563) 43– 4 DOI: 10.1038/nature14639
      There is no corresponding record for this reference.
    46. 46
      Horst, G. P.; Sarnelle, O.; White, J. D.; Hamilton, S. K.; Kaul, R. B.; Bressie, J. D. Nitrogen availability increases the toxin quota of a harmful cyanobacterium Water Res. 2014, 54, 188– 198 DOI: 10.1016/j.watres.2014.01.063
      There is no corresponding record for this reference.
    47. 47
      Downing, T. G.; Meyer, C.; Gehringer, M. M.; van de Venter, M. Microcystin content of Microcystis aeruginosa is modulated by nitrogen uptake rate relative to specific growth rate or carbon fixation rate Environ. Toxicol. 2005, 20 (3) 257– 262 DOI: 10.1002/tox.20106
      There is no corresponding record for this reference.
    48. 48
      Van de Waal, D. B.; Verspagen, J. M. H.; Lürling, M.; Van Donk, E.; Visser, P. M.; Huisman, J. The ecological stoichiometry of toxins produced by harmful cyanobacteria: an experimental test of the carbon-nutrient balance hypothesis Ecology Letters 2009, 12, 1326– 1335 DOI: 10.1111/j.1461-0248.2009.01383.x
      There is no corresponding record for this reference.
    49. 49
      Donald, D. B.; Bogard, M. J.; Finlay, K.; Leavitt, P. R. Comparative effects of urea, ammonium, and nitrate on phytoplankton abundance, community composition, and toxicity in hypereutrophic freshwaters Limnol. Oceanogr. 2011, 56 (6) 2161– 2175 DOI: 10.4319/lo.2011.56.6.2161
      49
      Comparative effects of urea, ammonium, and nitrate on phytoplankton abundance, community composition, and toxicity in hypereutrophic freshwaters
      Donald, Derek B.; Bogard, Matthew J.; Finlay, Kerri; Leavitt, Peter R.
      Limnology and Oceanography (2011), 56 (6), 2161-2175CODEN: LIOCAH; ISSN:0024-3590. (American Society of Limnology and Oceanography)
      Dissolved nitrogen (N) as urea ([NH2]2CO), nitrate (NO3-), and ammonium (NH4+) was added to naturally phosphorus (P)-rich lake water (up to 175 μg P L-1) to test the hypotheses that pollution of hypereutrophic lakes with N increases total algal abundance, alters community compn., and favors toxic cyanobacteria that do not fix atm. N2. Monthly expts. were conducted in triplicate in polymictic Wascana Lake, Saskatchewan, Canada, during July, August, and Sept. 2008 using large (> 3140 L) enclosures. Addn. of all forms of N added at 6 mg N L-1 increased total algal abundance (as chlorophyll a) by up to 350% relative to controls during August and Sept., when sol. reactive P (SRP) was > 50 μg P L-1 and dissolved N:P was < 20:1 by mass. In particular, NH4+ and urea favored non-heterocystous cyanobacteria and chlorophytes and NO3-, urea promoted chlorophytes, some cyanobacteria, and transient blooms of siliceous algae, whereas N2-fixing cyanobacteria and dinoflagellates exhibited little response to added N. Added N also increased microcystin prodn. by up to 13-fold in August and Sept., although the magnitude of response varied with N species and predominant algal taxon (Planktothrix agardhii, Microcystis spp.). These findings demonstrate that pollution with N intensifies eutrophication and algal toxicity in lakes with elevated concns. of SRP and low N:P, and that the magnitude of these effects depends on the chem. form, and hence source, of N.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3MXhs1yntL%252FL&md5=88f40ed75eef19cd20f4f47e5de0a6ae
    50. 50
      Finlay, K.; Patoine, A.; Donald, D. B.; Bogard, M. J.; Leavitt, P. R. Experimental evidence that pollution with urea can degrade water quality in phosphorus-rich lakes of the Northern Great Plains Limnol. Oceanogr. 2010, 55 (3) 1213– 1230 DOI: 10.4319/lo.2010.55.3.1213
      50
      Experimental evidence that pollution with urea can degrade water quality in phosphorus-rich lakes of the northern Great Plains
      Finlay, Kerri; Patoine, Alain; Donald, Derek B.; Bogard, Matthew J.; Leavitt, Peter R.
      Limnology and Oceanography (2010), 55 (3), 1213-1230CODEN: LIOCAH; ISSN:0024-3590. (American Society of Limnology and Oceanography)
      Urea is the most abundant nitrogen (N) fertilizer used on agricultural soils, yet its effects on adjacent aquatic ecosystems are largely unknown. Here 21-d, 3000-L mesocosm expts. were conducted monthly in a hypereutrophic lake during July-Sept. 2007 to quantify how addn. of urea might affect phytoplankton abundance, gross community compn., and algal toxicity in a phosphorus (P) -rich lake. Repeated measures anal. of variance demonstrated that addn. of sufficient urea to increase ratios of sol. N : P from ∼15:1 to >24:1 (by mass) also increased algal biomass (as Chlorophyll a) and microcystin concns. 200-400%, as non-N2-fixing but toxic cyanobacteria (Microcystis, Planktothrix) and less harmful chlorophytes (Micractinium, Oocystis) replaced colonial N2-fixing cyanobacteria (Anabaena, Aphanizomenon). No significant effects of urea amendment were recorded for trials in which N : P ratios were elevated at the start of the expt., or in which ambient light levels were reduced to 25 μmol quanta m-2 s-1, although preliminary evidence suggests that urea addn. stimulated growth of heterotrophic bacteria irresp. of light regime. Development of toxic non-N2-fixing cyanobacteria by N pollution of P-rich lakes is consistent with findings from whole-lake expts. and paleolimnol. studies of deep lakes, and suggests that the fertilization needed to feed 3 billion more people by 2050 may create conditions in which future water quality in P-replete regions is degraded further by urea export from farms and cities.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3cXotVWgu7s%253D&md5=aeb1ada0ba208efd23762de774a6f948
    51. 51
      Agrawal, M. K.; Bagchi, D.; Bagchi, S. N. Acute inhibition of protease and suppression of growth in zooplankter, Moina macrocopa, by Microcystis blooms collected in Central India Hydrobiologia 2001, 464 (1) 37– 44 DOI: 10.1023/A:1013946514556
      There is no corresponding record for this reference.
    52. 52
      Agrawal, M. K.; Zitt, A.; Bagchi, D.; Weckesser, J.; Bagchi, S. N.; von Elert, E. Characterization of proteases in guts of Daphnia magna and their inhibition by Microcystis aeruginosa PCC 7806 Environ. Toxicol. 2005, 20 (3) 314– 22 DOI: 10.1002/tox.20123
      There is no corresponding record for this reference.
    53. 53
      Gobler, C. J.; Davis, T. W.; Coyne, K. J.; Boyer, G. L. Interactive influences of nutrient loading, zooplankton grazing, and microcystin synthetase gene expression on cyanobacterial bloom dynamics in a eutrophic New York lake Harmful Algae 2007, 6 (1) 119– 133 DOI: 10.1016/j.hal.2006.08.003
      There is no corresponding record for this reference.
    54. 54
      Sunda, W. G.; Graneli, E.; Gobler, C. J. Positive feedback and the development and persistence of ecosystem disruptive algal blooms J. Phycol. 2006, 42 (5) 963– 974 DOI: 10.1111/j.1529-8817.2006.00261.x
      There is no corresponding record for this reference.
    55. 55
      Kromkamp, J. Formation and functional significance of storage products in cyanobacteria N. Z. J. Mar. Freshwater Res. 1987, 21 (3) 457– 465 DOI: 10.1080/00288330.1987.9516241
      55
      Formation and functional significance of storage products in cyanobacteria
      Kromkamp, Jacco
      New Zealand Journal of Marine and Freshwater Research (1987), 21 (3), 457-65CODEN: NZJMBS; ISSN:0028-8330.
      A review with 90 refs. The most common storage products of cyanobacteria are polyphosphate as a phosphorus storage compd., cyanophycin or phycobilin protein pigment as nitrogen storage products, and glycogen as a storage product of both carbon and energy. Nutrient uptake kinetics are regulated by the storage pools, and the patterns of regulation have a feedback effect on the amt. of accumulated nutrient in the cells. Besides having a storage function the nutrient storage products are likely to act as metabolic sinks during conditions of energy stress. Regulation of storage products is esp. strict in light-limited cultures. By increasing the rate of polysaccharide formation during growth with short photoperiods, cyanobacteria are able to sustain relatively high growth rates. This effect is enhanced by keeping respiratory losses very low.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaL1cXktlCqsL4%253D&md5=2c54cd6d864f6e882fd2386154e11ab0
    56. 56
      Allen, M. M. Cyanobacterial cell inclusions Annu. Rev. Microbiol. 1984, 38, 1– 25 DOI: 10.1146/annurev.mi.38.100184.000245
      56
      Cyanobacterial cell inclusions
      Allen, Mary Mennes
      Annual Review of Microbiology (1984), 38 (), 1-25CODEN: ARMIAZ; ISSN:0066-4227.
      A review with 151 refs.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaL2cXmtVOhsbY%253D&md5=97e0621b56ff7af66dce85a1d38a85ea
    57. 57
      Martin, P.; Dyhrman, S. T.; Lomas, M. W.; Poulton, N. J.; Van Mooy, B. A. Accumulation and enhanced cycling of polyphosphate by Sargasso Sea plankton in response to low phosphorus Proc. Natl. Acad. Sci. U. S. A. 2014, 111 (22) 8089– 94 DOI: 10.1073/pnas.1321719111
      57
      Accumulation and enhanced cycling of polyphosphate by Sargasso Sea plankton in response to low phosphorus
      Martin, Patrick; Dyhrman, Sonya T.; Lomas, Michael W.; Poulton, Nicole J.; Van Mooy, Benjamin A. S.
      Proceedings of the National Academy of Sciences of the United States of America (2014), 111 (22), 8089-8094CODEN: PNASA6; ISSN:0027-8424. (National Academy of Sciences)
      Phytoplankton alter their biochem. compn. according to nutrient availability, such that their bulk elemental compn. varies across oceanic provinces. However, the links between plankton biochem. compn. and variation in biogeochem. cycling of nutrients remain largely unknown. In a survey of phytoplankton P stress in the western North Atlantic, we found that phytoplankton in the P-depleted subtropical Sargasso Sea were enriched in the biochem. polyphosphate (polyP) compared with nutrient-rich temperate waters, contradicting the canonical oceanog. view of polyP as a luxury P storage mol. The enrichment in polyP coincided with enhanced alk. phosphatase activity and substitution of sulfolipids for phospholipids, which are both indicators of P stress. PolyP appeared to be liberated preferentially over bulk P from sinking particles in the Sargasso Sea, thereby retaining P in shallow waters. Thus, polyP cycling may form a feedback loop that attenuates the export of P when it becomes scarce, contributes bioavailable P for primary prodn., and supports the export of C and N via sinking particles.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2cXmslegs7o%253D&md5=6f497e0f5c1bc90ecaf2b2ba69568ee0
    58. 58
      Allen, M. M.; Hutchison, F. Nitrogen limitation and recovery in the cyanobacterium Aphanocapsa 6308 Arch. Microbiol. 1980, 128 (1) 1– 7 DOI: 10.1007/BF00422297
      There is no corresponding record for this reference.
    59. 59
      Van de Waal, D. B.; Ferreruela, G.; Tonk, L.; Van Donk, E.; Huisman, J.; Visser, P. M.; Matthijs, H. C. P. Pulsed nitrogen supply induces dynamic changes in the amino acid composition and microcystin production of the harmful cyanobacterium Planktothrix agardhii FEMS Microbiol. Ecol. 2010, 74 (2) 430– 438 DOI: 10.1111/j.1574-6941.2010.00958.x
      There is no corresponding record for this reference.
    60. 60
      Dyhrman, S. T.; Jenkins, B. D.; Rynearson, T. A.; Saito, M. A.; Mercier, M. L.; Alexander, H.; Whitney, L. P.; Drzewianowski, A.; Bulygin, V. V.; Bertrand, E. M.; Wu, Z.; Benitez-Nelson, C.; Heithoff, A. The transcriptome and proteome of the diatom Thalassiosira pseudonana reveal a diverse phosphorus stress response PLoS One 2012, 7 (3) e33768 DOI: 10.1371/journal.pone.0033768
      60
      The transcriptome and proteome of the diatom Thalassiosira pseudonana reveal a diverse phosphorus stress response
      Dyhrman, Sonya T.; Jenkins, Bethany D.; Rynearson, Tatiana A.; Saito, Mak A.; Mercier, Melissa L.; Alexander, Harriet; Whitney, LeAnn P.; Drzewianowski, Andrea; Bulygin, Vladimir V.; Bertrand, Erin M.; Wu, Zhijin; Benitez-Nelson, Claudia; Heithoff, Abigail
      PLoS One (2012), 7 (3), e33768CODEN: POLNCL; ISSN:1932-6203. (Public Library of Science)
      P P is a crit. driver of phytoplankton growth and ecosystem function in the ocean. Diatoms are an abundant class of marine phytoplankton that are responsible for significant amts. of primary prodn. With the control they exert on the oceanic carbon cycle, there have been a no. of studies focused on how diatoms respond to limiting macro and micronutrients such as iron and nitrogen. However, diatom physiol. responses to P deficiency are poorly understood. Here, the authors couple deep sequencing of transcript tags and quant. proteomics to analyze the diatom Thalassiosira pseudonana grown under P-replete and P-deficient conditions. Some 318 transcripts were differentially regulated with a false discovery rate of <0.05, and a total of 136 proteins were differentially abundant (p<0.05). Significant changes in the abundance of transcripts and proteins were obsd. and coordinated for multiple biochem. pathways, including glycolysis and translation. Patterns in transcript and protein abundance were also linked to physiol. changes in cellular P distributions, and enzyme activities. These data demonstrate that diatom P deficiency results in changes in cellular P allocation through polyphosphate prodn., increased P transport, a switch to utilization of dissolved org. P through increased prodn. of metalloenzymes, and a remodeling of the cell surface through prodn. of sulfolipids. Thus, these findings reveal that T. pseudonana has evolved a sophisticated response to P deficiency involving multiple biochem. strategies that are likely crit. to its ability to respond to variations in environmental P availability.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC38XlsFamt7Y%253D&md5=62f28dcff317f0086344bdb264dd5a91
    61. 61
      Grillo, J. F.; Gibson, J. Regulation of phosphate accumulation in the unicellular cyanobacterium Synechococcus J. Bacteriol. 1979, 140 (2) 508– 517
      61
      Regulation of phosphate accumulation in the unicellular cyanobacterium Synechococcus
      Grillo, John F.; Gibson, Jane
      Journal of Bacteriology (1979), 140 (2), 508-17CODEN: JOBAAY; ISSN:0021-9193.
      The P contents of acid-sol. pools, lipid, RNA, and acid-insol. polyphosphate were lowered in Synechococcus in proportion to the redn. in growth rate in phosphate-limited but not in NO3--limited continuous culture. P in these cell fractions was lost proportionately during progressive phosphate starvation of batch cultures. Acid-insol. polyphosphate was always present in all cultural conditions to ∼10% of total cell P and did not turn over during balanced exponential growth. Extensive polyphosphate formation occurred transiently when phosphate was given to cells which had been phosphate limited. This material was broken down after 8 h even with excess external orthophosphate, and its P was transferred into other cell fractions, notably RNA. Phosphate uptake kinetics indicated an invariant apparent Km of about 0.5 μM, but Vmax was 40-50-fold greater in cells from phosphate-limited cultures than in cells from NO3--limited or balanced batch cultures. Over 90% of the phosphate taken up within the 1st 30 s at 15° was recovered as orthophosphate. The uptake process is highly specific, since neither phosphate entry nor growth was affected by a 100-fold excess of arsenate. The activity of polyphosphate synthetase in cell exts. increased ≥20-fold during phosphate starvation or in phosphate-restricted growth, but polyphosphatase activity was little changed by different growth conditions. Apparently, derepression of the phosphate transport and polyphosphate-synthesizing systems as well as alk. phosphatase occurs in phosphate shortage, but the breakdown of polyphosphate in this organism is regulated by modulation of existing enzyme activity.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaL3cXlsVyhug%253D%253D&md5=3e583267266198c27838e3129f318fd7
    62. 62
      Aziz, R. K.; Breitbart, M.; Edwards, R. A. Transposases are the most abundant, most ubiquitous genes in nature Nucleic Acids Res. 2010, 38 (13) 4207– 17 DOI: 10.1093/nar/gkq140
      There is no corresponding record for this reference.
    63. 63
      Casacuberta, E.; González, J. The impact of transposable elements in environmental adaptation Mol. Ecol. 2013, 22 (6) 1503– 17 DOI: 10.1111/mec.12170
      63
      The impact of transposable elements in environmental adaptation
      Casacuberta, Elena; Gonzalez, Josefa
      Molecular Ecology (2013), 22 (6), 1503-1517CODEN: MOECEO; ISSN:0962-1083. (Wiley-Blackwell)
      A review. Transposable elements (TEs) play an important role in the responsive capacity of their hosts in the face of environmental challenges. The variety of mechanisms by which TEs influence the capacity of adaptation of the host is as large as the variety of TEs and host genomes. For example, TEs might directly affect the function of individual genes, provide a mechanism for rapidly acquiring new genetic material and disseminate regulatory elements that can lead to the creation of stress-inducible regulatory networks. In this review, the authors summarize recent examples that are part of an increasing body of evidence suggesting a significant role of TEs in the host response to an ever-changing environment, both in prokaryote and in eukaryote organisms. They argue that in the near future, the increasing availability of genome sequences and the development of new tools to discover and analyze TE insertions will further show the relevant role of TEs in environmental adaptation.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3sXktFSrsb4%253D&md5=3afa435779861707d3f739bab9f1e6bc
    64. 64
      Lin, S.; Haas, S.; Zemojtel, T.; Xiao, P.; Vingron, M.; Li, R. Genome-wide comparison of cyanobacterial transposable elements, potential genetic diversity indicators Gene 2011, 473 (2) 139– 49 DOI: 10.1016/j.gene.2010.11.011
      There is no corresponding record for this reference.
    65. 65
      Frangeul, L.; Quillardet, P.; Castets, A.-M.; Humbert, J.-F.; Matthijs, H. C.; Cortez, D.; Tolonen, A.; Zhang, C.-C.; Gribaldo, S.; Kehr, J.-C.; Zilliges, Y.; Ziemert, N.; Becker, S.; Talla, E.; Latifi, A.; Billault, A.; Lepelletier, A.; Dittmann, E.; Bouchier, C.; Tandeau de Marsac, N. Highly plastic genome of Microcystis aeruginosa PCC 7806, a ubiquitous toxic freshwater cyanobacterium BMC Genomics 2008, 9, 274 DOI: 10.1186/1471-2164-9-274
      There is no corresponding record for this reference.
    66. 66
      Makarova, K. S.; Wolf, Y. I.; Snir, S.; Koonin, E. V. Defense islands in bacterial and archaeal genomes and prediction of novel defense systems J. Bacteriol. 2011, 193 (21) 6039– 56 DOI: 10.1128/JB.05535-11
      66
      Defense islands in bacterial and archaeal genomes and prediction of novel defense systems
      Makarova, Kira S.; Wolf, Yuri I.; Snir, Sagi; Koonin, Eugene V.
      Journal of Bacteriology (2011), 193 (21), 6039-6056CODEN: JOBAAY; ISSN:0021-9193. (American Society for Microbiology)
      The arms race between cellular life forms and viruses is a major driving force of evolution. A substantial fraction of bacterial and archaeal genomes is dedicated to antivirus defense. We analyzed the distribution of defense genes and typical mobilome components (such as viral and transposon genes) in bacterial and archaeal genomes and demonstrated statistically significant clustering of antivirus defense systems and mobile genes and elements in genomic islands. The defense islands are enriched in putative operons and contain numerous overrepresented gene families. A detailed sequence anal. of the proteins encoded by genes in these families shows that many of them are diverged variants of known defense system components, whereas others show features, such as characteristic operonic organization, that are suggestive of novel defense systems. Thus, genomic islands provide abundant material for the exptl. study of bacterial and archaeal antivirus defense. Except for the CRISPR-Cas systems, different classes of defense systems, in particular toxin-antitoxin and restriction-modification systems, show nonrandom clustering in defense islands. It remains unclear to what extent these assocns. reflect functional cooperation between different defense systems and to what extent the islands are genomic "sinks" that accumulate diverse nonessential genes, particularly those acquired via horizontal gene transfer. The characteristics of defense islands resemble those of mobilome islands. Defense and mobilome genes are nonrandomly assocd. in islands, suggesting nonadaptive evolution of the islands via a preferential attachment-like mechanism underpinned by the addictive properties of defense systems such as toxins-antitoxins and an important role of horizontal mobility in the evolution of these islands.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3MXhsVSqs7bL&md5=07983aca761b34173388946d653855eb
    67. 67
      Kuno, S.; Yoshida, T.; Kamikawa, R.; Hosoda, N.; Sako, Y. The distribution of a phage-related insertion sequence element in the cyanobacterium, Microcystis aeruginosa Microbes and Environments 2010, 25 (4) 295– 301 DOI: 10.1264/jsme2.ME10125
      There is no corresponding record for this reference.
    68. 68
      Fuhrman, J. A. Marine viruses and their biogeochemical and ecological effects Nature 1999, 399 (6736) 541– 548 DOI: 10.1038/21119
      68
      Marine viruses and their biogeochemical and ecological effects
      Fuhrman, Jed A.
      Nature (London) (1999), 399 (6736), 541-548CODEN: NATUAS; ISSN:0028-0836. (Macmillan Magazines)
      Viruses are the most common biol. agents in the sea, typically numbering ten billion per L. They probably infect all organisms, can undergo rapid decay and replenishment, and influence many biogeochem. and ecol. processes, Including nutrient cycling, system respiration, particle size-distributions and sinking rates, bacterial and algal biodiversity and species distributions, algal bloom control, di-Me sulfide formation and genetic transfer. Newly developed fluorescence and mol. techniques leave the field poised to make significant advances towards evaluating and quantifying such effects.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaK1MXjvFeiurk%253D&md5=ecdc1c87569573c736c8d95d9fc810f2
    69. 69
      Suttle, C. A. Marine viruses--major players in the global ecosystem Nat. Rev. Microbiol. 2007, 5 (10) 801– 12 DOI: 10.1038/nrmicro1750
      69
      Marine viruses-major players in the global ecosystem
      Suttle, Curtis A.
      Nature Reviews Microbiology (2007), 5 (10), 801-812CODEN: NRMACK; ISSN:1740-1526. (Nature Publishing Group)
      A review concerning current knowledge of marine viruses, highlighting areas in which marine virol. is quickly advancing or seems to be poised for paradigm-shifting discoveries is given. Topics discussed include: abundance of marine viruses; viruses, mortality, and elemental cycling; microbial community structures; invertebrate and vertebrate viruses; marine virus diversity (metagenomic approaches to viral diversity); diversity, viruses, and r and K selection (rank-abundance curves and active populations, r and K selection in the marine milieu); and conclusions.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD2sXhtVeis7nK&md5=762cb3987680619e9e8b6d5dd721b78e
    70. 70
      Wilhelm, S. W.; Carberry, M. J.; Eldridge, M. L.; Poorvin, L.; Saxton, M. A.; Doblin, M. A. Marine and freshwater cyanophages in a Laurentian Great Lake: evidence from infectivity assays and molecular analyses of g20 genes Appl. Environ. Microbiol. 2006, 72 (7) 4957– 63 DOI: 10.1128/AEM.00349-06
      There is no corresponding record for this reference.
    71. 71
      Manage, P. M.; Kawabata, Z.; Nakano, S. Dynamics of cyanophage-like particles and algicidal bacteria causing Microcystis aeruginosa mortality Limnology 2001, 2 (2) 73– 78 DOI: 10.1007/s102010170002
      There is no corresponding record for this reference.
    72. 72
      Tucker, S.; Pollard, P. Identification of cyanophage Ma-LBP and infection of the cyanobacterium Microcystis aeruginosa from an Australian subtropical lake by the virus Appl. Environ. Microbiol. 2005, 71 (2) 629– 35 DOI: 10.1128/AEM.71.2.629-635.2005
      72
      Identification of cyanophage Ma-LBP and infection of the cyanobacterium Microcystis aeruginosa from an Australian subtropical lake by the virus
      Tucker, Stephen; Pollard, Peter
      Applied and Environmental Microbiology (2005), 71 (2), 629-635CODEN: AEMIDF; ISSN:0099-2240. (American Society for Microbiology)
      Viruses can control the structure of bacterial communities in aquatic environments. The aim of this project was to det. if cyanophages (viruses specific to cyanobacteria) could exert a controlling influence on the abundance of the potentially toxic cyanobacterium Microcystis aeruginosa (host). M. aeruginosa was isolated, cultured, and characterized from a subtropical monomictic lake-Lake Baroon, Sunshine Coast, Queensland, Australia. The viral communities in the lake were sepd. from cyanobacterial grazers by filtration and chloroform washing. The natural lake viral cocktail was incubated with the M. aeruginosa host growing under optimal light and nutrient conditions. The specific growth rate of the host was 0.023 h-1; generation time, 30.2 h. Within 6 days, the host abundance decreased by 95%. The d. of the cyanophage was pos. correlated with the rate of M. aeruginosa cell lysis (r2 = 0.95). The cyanophage replication time was 11.2 h, with an av. burst size of 28 viral particles per host cell. However, in 3 wk, the cultured host community recovered, possibly because the host developed resistance (immunity) to the cyanophage. The multiplicity of infection was detd. to be 2,890 virus-like particles/cultured host cell, using an undiluted lake viral population. Transmission electron microscopy showed that two types of virus were likely controlling the host cyanobacterial abundance. Both viruses displayed T7-like morphol. and belonged to the Podoviridiae group (short tails) of viruses that we called cyanophage Ma-LBP. In Lake Baroon, the no. of the cyanophage Ma-LBP was 5.6 × 104 cyanophage · ml-1, representing 0.23% of the natural viral population of 2.46 × 107 · ml-1. Our results showed that this cyanophage could be a major natural control mechanism of M. aeruginosa abundance in aquatic ecosystems like Lake Baroon. Future studies of potentially toxic cyanobacterial blooms need to consider factors that influence cyanophage attachment, infectivity, and lysis of their host alongside the phys. and chem. parameters that drive cyanobacterial growth and prodn.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD2MXhsVKgsrc%253D&md5=ce95b49e33ada5aac374920e0bc54ba4
    73. 73
      Kuno, S.; Yoshida, T.; Kaneko, T.; Sako, Y. Intricate interactions between the bloom-forming cyanobacterium Microcystis aeruginosa and foreign genetic elements, revealed by diversified clustered regularly interspaced short palindromic repeat (CRISPR) signatures Appl. Environ. Microbiol. 2012, 78 (15) 5353– 60 DOI: 10.1128/AEM.00626-12
      There is no corresponding record for this reference.
    74. 74
      Clasen, J. L.; Elser, J. J. The effect of host Chlorella NC64A carbon: phosphorus ratio on the production of Paramecium bursaria Chlorella Virus-1 Freshwater Biol. 2007, 52 (1) 112– 122 DOI: 10.1111/j.1365-2427.2006.01677.x
      74
      The effect of host Chlorella NC64A carbon: phosphorus ratio on the production of Paramecium bursaria Chlorella Virus-1
      Clasen, Jessica L.; Elser, James J.
      Freshwater Biology (2007), 52 (1), 112-122CODEN: FWBLAB; ISSN:0046-5070. (Blackwell Publishing Ltd.)
      We used the freshwater alga Chlorella NC64A (Division Chlorophyta) and its virus Paramecium bursaria Chlorella virus-1 (PBCV-1) as a model system to test for potential stoichiometric constraints on a virus-host interaction. Media phosphorus concns. were manipulated to create Chlorella NC64A host cells with low (91 ± 23) or high (453 ± 246) C: P ratio. In contrast, the C: P ratio of PBCV-1, calcd. from its biochem. compn., was 17: 1. Stoichiometric theory predicts that infection success and postinfection viral prodn. should be depressed in high C: P cultures due to insufficient intracellular P for prodn. of P-rich viral particles. Consistent with this hypothesis, viral prodn. was strongly affected by host C: P ratio. While host C: P ratio did not affect viral attachment or the percentage of new viral particles that were infectious, in the low C: P Chlorella NC64A treatment, nine times more viruses were produced per infected cell than in the high C: P treatment (158 ± 138 vs. 18 ± 18), indicating that the low C: P cells were higher quality for PBCV-1 proliferation. This result implies that the stoichiometric quality of algal cells can have a major effect on host-virus population dynamics.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD2sXitVegsrs%253D&md5=e9b696c7dbd01c86ce38ac15d8c182a4
    75. 75
      Schwarz, R.; Forchhammer, K. Acclimation of unicellular cyanobacteria to macronutrient deficiency: emergence of a complex network of cellular responses Microbiology 2005, 151 (8) 2503 DOI: 10.1099/mic.0.27883-0
      There is no corresponding record for this reference.
    76. 76
      Kaczmarzyk, D.; Fulda, M. Fatty acid activation in cyanobacteria mediated by acyl-acyl carrier protein synthetase enables fatty acid recycling Plant Physiol. 2010, 152 (3) 1598– 610 DOI: 10.1104/pp.109.148007
      76
      Fatty acid activation in cyanobacteria mediated by acyl-acyl carrier protein synthetase enables fatty acid recycling
      Kaczmarzyk, Danuta; Fulda, Martin
      Plant Physiology (2010), 152 (3), 1598-1610CODEN: PLPHAY; ISSN:0032-0889. (American Society of Plant Biologists)
      In cyanobacteria, fatty acids destined for lipid synthesis can be synthesized de novo, but also exogenous free fatty acids from the culture medium can be directly incorporated into lipids. Activation of exogenous fatty acids is likely required prior to their utilization. To identify the enzymic activity responsible for activation we cloned candidate genes from Synechocystis sp. PCC 6803 and Synechococcus elongatus PCC 7942 and identified the encoded proteins as acyl-acyl carrier protein synthetases (Aas). The enzymes catalyze the ATP-dependent esterification of fatty acids to the thiol of acyl carrier protein. The two protein sequences are only distantly related to known prokaryotic Aas proteins but they display strong similarity to sequences that can be found in almost all organisms that perform oxygenic photosynthesis. To investigate the biol. role of Aas activity in cyanobacteria, aas knockout mutants were generated in the background of Synechocystis sp. PCC 6803 and S. elongatus PCC 7942. The mutant strains showed two phenotypes characterized by the inability to utilize exogenous fatty acids and by the secretion of endogenous fatty acids into the culture medium. The analyses of extracellular and intracellular fatty acid profiles of aas mutant strains as well as labeling expts. indicated that the detected free fatty acids are released from membrane lipids. The data suggest a considerable turnover of lipid mols. and a role for Aas activity in recycling the released fatty acids. In this model, lipid degrdn. represents a third supply of fatty acids for lipid synthesis in cyanobacteria.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3cXmsF2ltrg%253D&md5=938bca49f80b01dbc675d3e4deb69fd9
    77. 77
      Postgate, J. R. Nitrogen Fixation. Cambridge University Press, Cambridge, U.K.; 1998, 3rd ed.
      There is no corresponding record for this reference.
    78. 78
      Moisander, P. H.; Cheshire, L. A.; Braddy, J.; Calandrino, E. S.; Hoffman, M.; Piehler, M. F.; Paerl, H. W. Facultative diazotrophy increases Cylindrospermopsis raciborskii competitiveness under fluctuating nitrogen availability FEMS Microbiol. Ecol. 2012, 79 (3) 800– 11 DOI: 10.1111/j.1574-6941.2011.01264.x
      There is no corresponding record for this reference.
    79. 79
      Granéli, E.; Turner, J. T. Ecology of Harmful Algae. Springer: Berlin Heidelberg, 2006.
      There is no corresponding record for this reference.
    80. 80
      Andersson, A.; Höglander, H.; Karlsson, C.; Huseby, S. Key role of phosphorus and nitrogen in regulating cyanobacterial community composition in the northern Baltic Sea Estuarine, Coastal Shelf Sci. 2015, 164, 161– 171 DOI: 10.1016/j.ecss.2015.07.013
      80
      Key role of phosphorus and nitrogen in regulating cyanobacterial community composition in the northern Baltic Sea
      Andersson, Agneta; Hoeglander, Helena; Karlsson, Chatarina; Huseby, Siv
      Estuarine, Coastal and Shelf Science (2015), 164 (), 161-171CODEN: ECSSD3; ISSN:0272-7714. (Elsevier Ltd.)
      Despite cyanobacteria being a key phytoplankton group in the Baltic Sea, the factors governing their community structure are still poorly understood. Here, we studied the occurrence of the orders Chroococcales, Oscillatoriales and Nostocales, and potentially explanatory variables at five locations in the northern Baltic Sea from June-Sept., 1998-2012. Cyanobacteria constituted 1-36% of the total phytoplankton biomass along the north-south gradient. In the Bothnian Bay, Chroococcales and Oscillatoriales dominated the cyanobacterial community, whereas in the Bothnian Sea and northern Baltic Proper, Nostocales was the dominant group. The dominance of Chroococcales was coupled to low salinity and low total phosphorus, whereas Oscillatoriales correlated with high total nitrogen and low salinity. Nostocales correlated to high total phosphorus, inorg. phosphorus and salinity. Chroococcales showed an increase over time in the offshore Bothnian Bay, whereas Nostocales increased in the coastal Bothnian Sea and coastal Baltic Proper. The increase of Nostocales in the coastal Bothnian Sea was explained by a rise in total phosphorus and decrease in dissolved inorg. nitrogen compared to an increase of total nitrogen and phosphorus in the coastal Baltic Proper. No significant trends were obsd. in the cyanobacterial community in the offshore Bothnian Sea and the offshore northern Baltic Proper. We concluded that Chroococcales may be a useful indicator for increased phosphorus levels in waters with low phosphorus concns., whereas Nostocales could be used as a quality indicator for increasing phosphorus concns. in waters with low inorg. N/P ratios (<20), such as in the coastal Bothnian Sea and Baltic Proper.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2MXhtlSisr3N&md5=61c044d1e41e414696213380e1979ffe
    81. 81
      Paerl, H. W.; Gardner, W. S.; McCarthy, M. J.; Peierls, B. L.; Wilhelm, S. W. Algal blooms: Noteworthy nitrogen Science 2014, 346 (6206) 175– 175 DOI: 10.1126/science.346.6206.175-a
      81
      Algal blooms: noteworthy nitrogen
      Paerl, Hans W.; Gardner, Wayne S.; McCarthy, Mark J.; Peierls, Benjamin L.; Wilheim, Steven W.
      Science (Washington, DC, United States) (2014), 346 (6206), 175CODEN: SCIEAS; ISSN:0036-8075. (American Association for the Advancement of Science)
      There is no expanded citation for this reference.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2cXhvVCgsrfL&md5=9daca74fc314e2f5c1c30f5fe55ca987

  • Supporting Information

    Supporting Information

    The Supporting Information is available free of charge on the ACS Publications website at DOI: 10.1021/acs.est.5b03931.

    • Tables showing physical, chemical, and community characterizing parameters measured at each station during September and October transects of the western basin of Lake Erie; nutrient concentrations [μM] for each station of the September and October transects of the western basin of Lake Erie; transcriptomic sequencing results; nutrient concentrations [μM] for each treatment for the nutrient amendment experiment; and the number of significantly differentially expressed genes for Microcystis within each functional category relative to the control. Figures showing a composite of MODIS Cyanobacterial Index images from the NOAA Experimental Lake Erie Harmful Algal Bloom Bulletin for 2013; the number of significant differentially expressed genes for Microcystis at each station relative to station LET7 and relative to the control after 48 hr; heat map of genes involved in nitrogen and phosphorous transport and metabolism and their significant differential expression at each station relative to LET7 and under each treatment relative to the control for Microcystis; heat map of transposase genes and their significant differential expression at each station relative to LET7 for Microcystis; cyanobacterial abundance during the October transect of the western basin of Lake Erie for the three genera discussed; the number of significant differentially expressed genes in Planktothrix agaradhii NIVA-CYA 15; the number of significant differentially expressed genes in Anabaena sp. PCC7108; heat map of transposase genes and their significant differential expression relative to the control for Microcystis; heat map of genes involved in DNA replication, restriction, modification, recombination, and repair and their significant differential expression at each station relative to LET7 and under each treatment relative to the control for Microcystis; community analysis via Metaphlan displaying the average percent abundance across two biological replicates for the nutrient enrichment experiments; the number of significant differentially expressed transposase genes. (PDF)


    Terms & Conditions

    Most electronic Supporting Information files are available without a subscription to ACS Web Editions. Such files may be downloaded by article for research use (if there is a public use license linked to the relevant article, that license may permit other uses). Permission may be obtained from ACS for other uses through requests via the RightsLink permission system: http://pubs.acs.org/page/copyright/permissions.html.