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Updated: Jun 21, 2025

From a Natural Product to Its Biosynthetic Gene Cluster: A Demonstration Using Polyketomycin from Streptomyces diastatochromogenes Tü6028
Published on: January 13, 2017
A Bifunctional Methyltransferase in Biosynthesis of Antitumor Antibiotic Streptonigrin
Xiaozheng Wang1, Xinyue Xie1, Jing Wo1,2
1State Key Laboratory of Microbial Metabolism, Joint International Laboratory of Metabolic & Developmental Sciences, School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, 200240, Shanghai, China.
Abstract:
Streptonigrin (STN, 1) is a highly functionalized aminoquinone alkaloid antibiotic with broad and potent antitumor activity. STN structurally contains four methyl groups belonging to two types: C-methyl group and O-methyl groups. Here, we report the biochemical characterization of the O-methyltransferase StnQ2 that can catalyze both the methylation of a hydroxyl group and a carboxyl group in the biosynthesis of streptonigrin. This work not only provides a new insight into methyltransferases, but also advances the elucidation of the complete biosynthetic pathway of streptonigrin.
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