Insights into the catalysis of a lysine-tryptophan bond in bacterial peptides by a SPASM domain radical <i>S</i>-adenosylmethionine (SAM) peptide cyclase.

ABSTRACT: Radical S-adenosylmethionine (SAM) enzymes are emerging as a major superfamily of biological catalysts involved in the biosynthesis of the broad family of bioactive peptides called ribosomally synthesized and post-translationally modified peptides (RiPPs). These enzymes have been shown to catalyze unconventional reactions, such as methyl transfer to electrophilic carbon atoms, sulfur to C_α atom thioether bonds, or carbon-carbon bond formation. Recently, a novel radical SAM enzyme catalyzing the formation of a lysine-tryptophan bond has been identified in Streptococcus thermophilus, and a reaction mechanism has been proposed. By combining site-directed mutagenesis, biochemical assays, and spectroscopic analyses, we show here that this enzyme, belonging to the emergi

SUBMITTER: Benjdia A 

PROVIDER: S-EPMC5491770 | biostudies-literature | 2017 Jun

REPOSITORIES: biostudies-literature