Structural elucidation of the specific capsular polysaccharide of Rhodococcus equi serotype 7.
Structural analysis of the specific capsular polysaccharide produced by Rhodococcus equi serotype 7 indicated it to be a high-molecular-weight polymer consisting of equal molar amounts of D-galactose, D-mannose, L-rhamnose, and pyruvic acid. By employing a combination of chemical and NMR techniques, it was established that the polysaccharide is composed of the linear repeating trisaccharide units: [formula: see text] -->3)-alpha-D-Galp-(1-->3)-alpha-D-Manp-(1-->3)-alpha-L-Rhap -(1-->, in which the cyclic pyruvic acid acetal groups bridging the O-4 and O-6 positions of the alpha-D-Manp residues have the S-configuration. The 1H and 13C NMR spectra of the native and pyruvic acetal-free polysaccharides were fully assigned.
Masoud
H
H
Institute for Biological Sciences, National Research Council of Canada, Ottawa, Ontario.
Richards
J C
JC
D016667:Bacterial Capsules / Q000737:chemistry*; D002240:Carbohydrate Sequence; D002247:Carbon Isotopes; D005690:Galactose / Q000032:analysis; D009682:Magnetic Resonance Spectroscopy; D008358:Mannose / Q000032:analysis; D008969:Molecular Sequence Data; D011135:Polysaccharides, Bacterial / Q000737:chemistry* / Q000302:isolation & purification; D011522:Protons; D011773:Pyruvates / Q000032:analysis; D019289:Pyruvic Acid; D012210:Rhamnose / Q000032:analysis; D016929:Rhodococcus equi / Q000737:chemistry* / Q000276:immunology; D017421:Sequence Analysis
D002247:Carbon Isotopes; D011135:Polysaccharides, Bacterial; D011522:Protons; D011773:Pyruvates; D019289:Pyruvic Acid; D008358:Mannose; D012210:Rhamnose; D005690:Galactose