title: Structure and gene cluster of the O-antigen of Escherichia coli O165 containing 5-N-acetyl-7-N-[(R)-3-hydroxybutanoyl]pseudaminic acid.
abstract: Upon mild acid degradation of the lipopolysaccharide of Escherichia coli O165, the O-polysaccharide chain was cleaved at the glycosidic linkage of 5-N-acetyl-7-N-[(R)-3-hydroxybutanoyl]pseudaminic acid (Pse5Hb7Ac). Analysis of the resulting linear tetrasaccharide and alkali-treated lipopolysaccharide by (1)H/(13)C 1D and 2D nuclear magnetic resonance spectroscopy enabled elucidation of the following structure of the O-polysaccharide: →8)-α-Psep5Hb7Ac-(2 → 6)-β-d-Galp-(1 → 4)-β-d-Glсp-(1 → 3)-α-d-GlсpNAc-(1→. The β-d-Galp-(1 → 4)-β-d-Glсp-(1 → 3)-d-GlсpNAc structural element is also present in the O-polysaccharide of E. coli O82. The content of the O-antigen gene cluster of E. coli O165 was found to be consistent with the O-polysaccharide structure established. Functions of proteins encoded in the gene cluster, including enzymes involved in the Pse5Hb7Ac biosynthesis and glycosyltransferases, were putatively assigned by comparison with sequences in available databases.
authors.affiliation: N.D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, 119991 Moscow, Russian Federation.
authors.forename: Sof'ya N
authors.initials: SN
authors.lastname: Senchenkova
authors.affiliation: TEDA Institute of Biological Sciences and Biotechnology, Nankai University, TEDA, 300457 Tianjin, China.
authors.forename: Yuanyuan
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: N.D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, 119991 Moscow, Russian Federation.
authors.forename: Andrei V
authors.initials: AV
authors.lastname: Perepelov
authors.affiliation: TEDA Institute of Biological Sciences and Biotechnology, Nankai University, TEDA, 300457 Tianjin, China.
authors.forename: Xi
authors.initials: X
authors.lastname: Guo
authors.affiliation: N.D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, 119991 Moscow, Russian Federation.
authors.forename: Alexander S
authors.initials: AS
authors.lastname: Shashkov
authors.affiliation: Department of Laboratory Medicine, Division of Clinical Microbiology, Karolinska Institute, Karolinska University Hospital, S-141 86 Stockholm, Sweden.
authors.forename: Andrej
authors.initials: A
authors.lastname: Weintraub
authors.affiliation: TEDA Institute of Biological Sciences and Biotechnology, Nankai University, TEDA, 300457 Tianjin, China.
authors.forename: Bin
authors.initials: B
authors.lastname: Liu
authors.affiliation: Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, S-106 91 Stockholm, Sweden goran.widmalm@su.se.
authors.forename: Göran
authors.initials: G
authors.lastname: Widmalm
authors.affiliation: N.D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, 119991 Moscow, Russian Federation.
authors.forename: Yuriy A
authors.initials: YA
authors.lastname: Knirel
mesh_terms: D002240:Carbohydrate Sequence / Q000235:genetics; D004926:Escherichia coli / Q000235:genetics; D016695:Glycosyltransferases / Q000737:chemistry / Q000235:genetics*; D008070:Lipopolysaccharides; D009682:Magnetic Resonance Spectroscopy; D005810:Multigene Family; D019081:O Antigens / Q000737:chemistry* / Q000235:genetics; D012794:Sialic Acids / Q000737:chemistry* / Q000235:genetics; D013400:Sugar Acids / Q000737:chemistry*
chemical_list: C513444:5,7-diacetamido-3,5,7,9-tetradeoxynonulosonic acid; D008070:Lipopolysaccharides; D019081:O Antigens; D012794:Sialic Acids; D013400:Sugar Acids; D016695:Glycosyltransferases
keywords: Escherichia coli; O-antigen gene cluster; bacterial polysaccharide structure; lipopolysaccharide