title: Two different O-polysaccharides from Escherichia coli O86 are produced by different polymerization of the same O-repeating unit.
abstract: The structure of a new O-polysaccharide from Escherichia coli O86:K62:B7 was determined using NMR and methylation analysis. The structure is as follows: [carbohydrate: see text]. Comparison with the previously published structure from E. coli O86:K2:H2 revealed that the O-polysaccharides from these two E. coli O86 serotypes share the same branched pentasaccharide repeating unit. However, they differ in the anomeric configuration of the linkage, the linkage position, and the identity of the residue through which polymerization occurs. The immunochemical activity of these two forms of LPS toward anti-B antibody was studied and compared. The results showed that LPS from E. coli O86:K2:H2 strain possesses higher blood group B reactivity. The immunoreactivity difference was explained by modeling of the O-repeating unit tetrasaccharide fragments. This finding provides a good system for the further study of O-polysaccharide biosynthesis especially the repeating unit polymerization mechanism.
authors.affiliation: Department of Biochemistry, The Ohio State University, Columbus, OH 43210, USA.
authors.forename: Wen
authors.initials: W
authors.lastname: Yi
authors.forename: Peter
authors.initials: P
authors.lastname: Bystricky
authors.forename: Qingjia
authors.initials: Q
authors.lastname: Yao
authors.forename: Hongjie
authors.initials: H
authors.lastname: Guo
authors.forename: Lizhi
authors.initials: L
authors.lastname: Zhu
authors.forename: Hanfen
authors.initials: H
authors.lastname: Li
authors.forename: Jie
authors.initials: J
authors.lastname: Shen
authors.forename: Mei
authors.initials: M
authors.lastname: Li
authors.forename: Soumya
authors.initials: S
authors.lastname: Ganguly
authors.forename: C Allen
authors.initials: CA
authors.lastname: Bush
authors.forename: Peng G
authors.initials: PG
authors.lastname: Wang
mesh_terms: D000017:ABO Blood-Group System / Q000276:immunology; D000937:Antigen-Antibody Reactions; D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D004926:Escherichia coli / Q000276:immunology* / Q000378:metabolism*; D006801:Humans; D007536:Isomerism; D008958:Models, Molecular; D008969:Molecular Sequence Data; D019906:Nuclear Magnetic Resonance, Biomolecular; D019081:O Antigens / Q000096:biosynthesis* / Q000737:chemistry / Q000302:isolation & purification
chemical_list: D000017:ABO Blood-Group System; D019081:O Antigens