Discovery of glycerol phosphate and an immunogenic glycan motif in rhamnose-rich polysaccharides of Streptococcus uberis.

ABSTRACT: Streptococcus uberis is a causative pathogen of bovine mastitis with high genetic diversity. Rhamnose-rich polysaccharides (RPS) are abundant surface structures covalently anchored to peptidoglycan and represent promising vaccine candidates for several streptococcal pathogens. It was previously reported that the RPS of S. uberis strain 233 is composed of a repeating → 2)-α-L-Rhap-(1 → 3)-α-L-Rhap-(1 → disaccharide backbone decorated with α-D-Glcp side-chains. In this study, we identified a hitherto unknown glycerol phosphate (GroP) modification at the 6-OH of the Glc residue in S. uberis 233 RPS using nuclear magnetic resonance analysis. Comparative genomic analysis of 592 S. uberis genomes revealed significant diversity in the RPS biosynthesis gene cluster with six major RPS genotypes. RP

SUBMITTER: Shi Y 

PROVIDER: S-EPMC12235971 | biostudies-literature | 2025 Jul

REPOSITORIES: biostudies-literature