Two-Enzyme Pathway Links l-Arginine to Nitric Oxide in N-Nitroso BiosynthesisClick to copy article linkArticle link copied!
- Hai-Yan HeHai-Yan HeDepartment of Chemistry, University of British Columbia, Vancouver, CanadaMore by Hai-Yan He
- Alyssa C. HendersonAlyssa C. HendersonDepartment of Chemistry, University of British Columbia, Vancouver, CanadaMore by Alyssa C. Henderson
- Yi-Ling DuYi-Ling DuInstitute of Pharmaceutical Biotechnology, Zhejiang University School of Medicine, Hangzhou, ChinaMore by Yi-Ling Du
- Katherine S. Ryan*Katherine S. Ryan*[email protected]Department of Chemistry, University of British Columbia, Vancouver, CanadaMore by Katherine S. Ryan
Abstract
Nitric oxide (NO) has wide-ranging roles in biology, but less is known about its role in building chemical diversity. Here we report a new route to NO from the biosynthetic pathway to the N-nitroso compound streptozocin. We show that the N-nitroso group of streptozocin comes from the biosynthetic reassembly of l-arginine, with the guanidino nitrogens forming a nitrogen–nitrogen bond. To understand this biosynthetic process, we identify the biosynthetic gene cluster of streptozocin and demonstrate that free l-arginine is N-methylated by StzE to give Nω-monomethyl-l-arginine. We show that this product is then oxidized by StzF, a nonheme iron-dependent enzyme unrelated to known nitric oxide synthases, generating a urea compound and NO. Our work implies that formation and capture of NO is the likely route to N-nitroso formation in vivo. Altogether, our work unveils a new enzyme pair for the production of NO from l-arginine and sets the stage for understanding biosynthetic routes to N-nitroso natural products.
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