THE STRUCTURE OF THE LIPOPOLYSACCHARIDE O-ANTIGEN FROM YERSINIA-RUCKERI SEROTYPE-01

The O antigen obtained from the lipopolysaccharide of Yersinia ruckeri serotype 01, by mild acid hydrolysis, is composed of a branched tetrasaccharide repeating unit containing 2-acetamidino-2,6-dideoxy-L-galactose (L-FucAm), 2-acetamido-2-deoxy-D-glucose (D-GlcNAc), and 7-acetamido-3,5,7,9-tetradeoxy-5-(4-hydroxybutyramido)-D-glycero-L-galacto-nonulosonic acid (L-Sug). Partial hydrolysis of the O antigen with 0.1 M HClafforded a trisaccharide and a tetrasaccharide having nonulosonic acid at their reducing ends. Cleavage of the O antigen with anhydrous methanolic hydrogen fluoride afforded the methyl glycoside derivatives of a trisaccharide and a tetrasaccharide. H-1 and C-13 NMR analysis, including H-1-C-13 heteronuclear multiple bond correlation spectroscopy to locate the N-acyl substituents, together with mass spectrometric analysis of the above oligosaccharides, allowed the structure of the O-specific polysaccharide to be assigned as: [GRAPHICS] t the presence of the fucose branches does not alter the length of the repetitive units which compose the central core of chondroitin from sea cucumber. These results are consistent with the chemical studies of these two polysaccharides.