title: Structures of the O-antigens of Escherichia coli O13, O129, and O135 related to the O-antigens of Shigella flexneri.
abstract: O-Polysaccharides (O-antigens) were isolated from Escherichia coli O13, O129, and O135 and studied by chemical analyses along with 2D (1)H and (13)C NMR spectroscopy. They were found to possess a common -->2)-l-Rha-(alpha1-->2)-l-Rha-(alpha1-->3)-l-Rha-(alpha1-->3)-d-GlcNAc-(beta1--> backbone, which is a characteristic structural motif of the O-polysaccharides of Shigella flexneri types 1-5. In both the bacterial species, the backbone is decorated with lateral glucose residues or/and O-acetyl groups. In E. coli O13, a new site of glycosylation on 3-substituted Rha was revealed and the following O-polysaccharide structure was established: The structure of the E. coli O129 antigen was found to be identical to the O-antigen structure of S. flexneri type 5a specified in this work and that of E. coli O135 to S. flexneri type 4b reported earlier.
authors.affiliation: N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow, Russian Federation. perepel@ioc.ac.ru
authors.forename: Andrei V
authors.initials: AV
authors.lastname: Perepelov
authors.forename: Sergei D
authors.initials: SD
authors.lastname: Shevelev
authors.forename: Bin
authors.initials: B
authors.lastname: Liu
authors.forename: Sof'ya N
authors.initials: SN
authors.lastname: Senchenkova
authors.forename: Alexander S
authors.initials: AS
authors.lastname: Shashkov
authors.forename: Lu
authors.initials: L
authors.lastname: Feng
authors.forename: Yuriy A
authors.initials: YA
authors.lastname: Knirel
authors.forename: Lei
authors.initials: L
authors.lastname: Wang
mesh_terms: D000107:Acetylation; D002240:Carbohydrate Sequence; D004926:Escherichia coli / Q000737:chemistry* / Q000145:classification*; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D019081:O Antigens / Q000737:chemistry*; D010100:Oxygen / Q000737:chemistry; D012763:Shigella flexneri / Q000737:chemistry*
chemical_list: D019081:O Antigens; D010100:Oxygen