Zha, LiJiang, YindiHenke, Matthew T.Wilson, MatthewWang, Jennifer X.Kelleher, Neil L.Balskus, Emily2018-03-202017Zha, Li, Yindi Jiang, Matthew T. Henke, Matthew R. Wilson, Jennifer X. Wang, Neil L. Kelleher, and Emily P. Balskus. 2017. “Colibactin assembly line enzymes use S-adenosylmethionine to build a cyclopropane ring.” Nature chemical biology 13 (10): 1063-1065. doi:10.1038/nchembio.2448. http://dx.doi.org/10.1038/nchembio.2448.http://nrs.harvard.edu/urn-3:HUL.InstRepos:35015083Despite containing an α-amino acid, the versatile cofactor S-adenosylmethionine (SAM) is not a known building block for non-ribosomal peptide synthetase (NRPS) assembly lines. Here we report an unusual NRPS module from colibactin biosynthesis that uses SAM for amide bond formation and subsequent cyclopropanation. Our findings showcase a new use for SAM and reveal a novel biosynthetic route to a functional group that likely mediates colibactin’s genotoxicity.en-USJournal Article2018-03-2010.1038/nchembio.2448