title: Structural studies of the Escherichia coli K93 and K53 capsular polysaccharides.
abstract: The structures of the Escherichia coli K93 and K53 capsular polysaccharides have been investigated by chemical and spectroscopic methods. The repeating unit of both polymers was found to be----3)-beta-D-Galf-(1----f)-beta-D-GlcAp-(1. The O-5 and O-6 atoms of D-galactose are acetylated in the repeating unit of the K93 polymer, but only O-2 is acetylated in the K53 polymer. The K93 polysaccharide is cross-reactive with the Neisseria meningitidis Group A capsular polysaccharide (of known structure). The K53 polysaccharide, although structurally similar to that from K93 organisms, does not cross-react with the Group A polymer.
mesh_terms: D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D004926:Escherichia coli / Q000276:immunology*; D005779:Immunodiffusion; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D011135:Polysaccharides, Bacterial
chemical_list: D011135:Polysaccharides, Bacterial