Characterization of S-glycosylated glycocins containing three disulfides.

ABSTRACT: Glycocins are a growing family of ribosomally synthesized and posttranslationally modified peptides (RiPPs) that are O- and/or S-glycosylated. Using a sequence similarity network of putative glycosyltransferases, the thg biosynthetic gene cluster (BGC) was identified in the genome of Thermoanaerobacterium thermosaccharolyticum. Heterologous expression in Escherichia coli showed that the glycosyltransferase (ThgS) encoded in the BGC adds N-acetyl-glucosamine (GlcNAc) to Ser and Cys residues of ThgA. The peptide derived from ThgA, which we name thermoglycocin, was structurally characterized and shown to resemble glycocin F. In addition to two nested disulfide bonds also present in glycocin F, thermoglycocin contains a third disulfide bond creating a C-terminal loop. Unexpectedly, ThgA lacks

SUBMITTER: Martini RM 

PROVIDER: S-EPMC12457901 | biostudies-literature | 2024 Dec

REPOSITORIES: biostudies-literature