Structural determination and immunochemical characterization of the type V group B Streptococcus capsular polysaccharide.
The type V capsular polysaccharide of group B Streptococcus has been isolated and purified, and its repeating unit structure determined. The native type V polysaccharide contains D-glucose, D-galactose, 2-acetamido-2-deoxy-D-glucose, and sialic acid in a molar ratio of 3:2:1:1. Methylation analysis and 1H NMR and 13C NMR analysis of the native type V polysaccharide and of its specifically degraded products permitted the determination of the repeating unit structure of the type V polysaccharide: [formula: see text] The type V polysaccharide has certain structural features in common with other group B streptococcal capsular polysaccharides but is antigenically distinct: no immunologic cross-reactivity was observed between type V and types Ia, Ib, II, III, or IV polysaccharides. Studies of antibody binding to the partially degraded forms of the type V polysaccharide indicated that the native epitope is complex, involving most if not all of the sugar residues of the repeating unit.
Wessels
M R
MR
Channing Laboratory, Brigham and Women's Hospital, Boston, Massachusetts 02115.
DiFabio
J L
JL
Benedì
V J
VJ
Kasper
D L
DL
Michon
F
F
Brisson
J R
JR
Jelínková
J
J
Jennings
H J
HJ
D016667:Bacterial Capsules; D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D007202:Indicators and Reagents; D009682:Magnetic Resonance Spectroscopy; D008745:Methylation; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011135:Polysaccharides, Bacterial / Q000737:chemistry / Q000276:immunology / Q000302:isolation & purification; D013292:Streptococcus agalactiae
D007202:Indicators and Reagents; D011135:Polysaccharides, Bacterial; C068312:capsular polysaccharide, streptoccal group B type V