Structural and genetic diversity of group B streptococcus capsular polysaccharides.

ABSTRACT: Group B Streptococcus (GBS) is an important pathogen of neonates, pregnant women, and immunocompromised individuals. GBS isolates associated with human infection produce one of nine antigenically distinct capsular polysaccharides which are thought to play a key role in virulence. A comparison of GBS polysaccharide structures of all nine known GBS serotypes together with the predicted amino acid sequences of the proteins that direct their synthesis suggests that the evolution of serotype-specific capsular polysaccharides has proceeded through en bloc replacement of individual glycosyltransferase genes with DNA sequences that encode enzymes with new linkage specificities. We found striking heterogeneity in amino acid sequences of synthetic enzymes with very similar functions, an observation

SUBMITTER: Cieslewicz MJ 

PROVIDER: S-EPMC1087335 | biostudies-literature | 2005 May

REPOSITORIES: biostudies-literature