Structure of the Capsular Polysaccharide of Vibrio cholerae O139 Synonym Bengal Containing D-galactose 4,6-Cyclophosphate

Abstract

The capsular polysaccharide (CPS) of Vibrio cholerae 0139 synonym Bengal, which is thought to carry determinants of 0-specificity, was isolated by phenol/water extraction followed by delipidation of the contaminating lipopolysaccharide at pH 4.2 and gel-permeation chromatography. The CPS contained, and phosphate. The CPS was studied by NMR spectroscopy, methylation analysis, and selective degradations, including partial acid hydrolysis at pH 3.1 and dephosphorylation with aqueous 48 % hydrofluoric acid, which both resulted in complete cleavage of Col. It was concluded that the CPS is built up of hexasaccharide repeating units containing inter alia D-galaCtOSe 4,6-cyclophosphate and having the following structureThese data basically confirm the structure of the K cholerae CPS proposed on the basis of an NMR study [L. M. Preston et al. (1995) J. Bacteriol. 177, and specify exactly the absolute configurations of the constituent monosaccharides and the position of the cyclic phosphate.

Structural analysis of the sheath of a sheathed bacterium, Leptothrix cholodnii

“…The coupling constants, 3 J 2,3 , 3 J 3,4 and 3 J 4,5 , of residue D were 10.9, 2.9 and 1.8 Hz, respectively. These values coincide with those of the ␣-galacto sugars [30,31] and residue D is concluded to be 2-amino-2-deoxygalacturonic acid (GalNA). Further analysis is required to determine its configuration.…”

Structural elucidation of the O-antigenic polysaccharide from Escherichia coli O175

“…Contaminating nucleic acids were removed by ultracentrifugation (100,000Âg, 4 h, 4°C). Lipid-free polysaccharide (PS) was prepared by treatment of the LPS with 0.1 M sodium acetate, pH 4.2, at 100°C for 5 h. 18 Lipid A was removed by centrifugation (10,000Âg, 20 min, 4°C). The PS was further purified by gel-permeation chromatography.…”

Polysaccharide biological response modifiers

“…In general, CPs are composed of single monosaccharide repeating units [18] or oligosaccharide repeating subunits. The oligosaccharide repeating unit can be disaccharide [19], trisaccharide [20][21][22], tetrasaccharide [23,24], pentasaccharide [25][26][27][28][29][30], and hexasaccharide [31][32][33]. The monosaccharides are usually modified with N-acetylation [31][32][33][34][35], carboxylation [31][32][33][34][35], and occasionally phosphorylation [32].…”