title: Structure of the polysaccharide O-antigen of Salmonella riogrande O:40 (group R) related to blood group A activity.
abstract: The structure of the Salmonella O:40 (Group R) antigen was determined from an analysis of the antigenic O-polysaccharide component of the lipopolysaccharide produced by Salmonella riogrande O:40. Using 1H- and 13C-NMR spectroscopy, methylation analysis, and periodate degradation methods, the O-polysaccharide was found to be a high molecular weight branched polymer of repeating pentasaccharide units having the structure: [formula: see text] The reported human blood group A activity was concluded to reside in an epitope of a terminal trisaccharide portion of the O-chain involving alpha-D-GalpNAc and beta-D-GlcpNAc residues linked (1----3) and (1----2), respectively, to beta-D-Manp branched residues in which the alpha-D-GalpNAc residue would appear to be the critical antigenic factor recognized by polyclonal blood group A antisera.
authors.affiliation: Institute for Biological Sciences, National Research Council, Ottawa, Ontario, Canada.
authors.forename: M B
authors.initials: MB
authors.lastname: Perry
authors.forename: L L
authors.initials: LL
authors.lastname: MacLean
mesh_terms: D000017:ABO Blood-Group System / Q000737:chemistry* / Q000276:immunology; D002240:Carbohydrate Sequence; D000939:Epitopes / Q000737:chemistry*; D008070:Lipopolysaccharides / Q000737:chemistry / Q000276:immunology; D008969:Molecular Sequence Data; D019081:O Antigens; D011135:Polysaccharides, Bacterial / Q000737:chemistry*; D012475:Salmonella / Q000737:chemistry / Q000276:immunology*
chemical_list: D000017:ABO Blood-Group System; D000939:Epitopes; D008070:Lipopolysaccharides; D019081:O Antigens; D011135:Polysaccharides, Bacterial