title: Structural studies of the O-antigenic polysaccharides from Shigella dysenteriae type 3 and Escherichia coli O124, a reinvestigation.
abstract: The structures of the O-antigenic part of the lipopolysaccharides from Shigella dysenteriae type 3 and Escherichia coli O124 have been reinvestigated. (1)H and (13)C NMR spectroscopy in combination with selected 2D NMR techniques were used to determine the O-antigen pentasaccharide repeating units with the following structure: [see text]. From biosynthetic considerations this should also be the biological repeating unit. The structures of the repeating units also explain the previously observed cross-reactivity between the strains and to E. coli O164, which only differs in the terminal sugar residue that is lacking the (R)-1-carboxyethyl group.
authors.affiliation: Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, S-106 91 Stockholm, Sweden.
authors.forename: K Hanna M
authors.initials: KH
authors.lastname: Jonsson
authors.forename: Andrej
authors.initials: A
authors.lastname: Weintraub
authors.forename: Göran
authors.initials: G
authors.lastname: Widmalm
mesh_terms: D002240:Carbohydrate Sequence; D004926:Escherichia coli / Q000737:chemistry*; D008969:Molecular Sequence Data; D019906:Nuclear Magnetic Resonance, Biomolecular; D019081:O Antigens / Q000737:chemistry*; D012762:Shigella dysenteriae / Q000737:chemistry*
chemical_list: D019081:O Antigens