Structural basis for iterative methylation by a cobalamin-dependent radical S-adenosylmethionine enzyme in cystobactamids biosynthesis

Proceedings of the National Academy of Sciences, Volume 123, Number 4, January 2026.
ImportanceCbl-dependent radical SAM methylases (RSMs) use two SAM molecules to methylate unactivated carbons. A SAM is used to methylate the alamin cob(I), thereby generating methylcobalamin (MeCbl). A second SAM molecule is used to generate a 5′-deoxyadenosyl…