title: Structure elucidation of the O-Antigen of Salmonella enterica O51 and its structural and genetic relation to the O-Antigen of Escherichia coli O23.
abstract: The O-polysaccharide (O-antigen) of Salmonella enterica O51 was isolated by mild acid degradation of the lipopolysaccharide and its structure was established using sugar analysis and NMR spectroscopy. The O-antigen of Escherichia coli O23, whose structure was elucidated earlier, possesses a similar structure and differs only in the presence of an additional lateral α-D-Glcp residue at position 6 of the GlcNAc residue in the main chain. Sequencing of the O-antigen gene clusters of S. enterica O51 and E. coli O23 revealed the same genes with a high-level similarity. By comparison with opened gene databases, all genes expected for the synthesis of the common structure of the two O-antigens were assigned functions. It is suggested that the gene clusters of both bacteria originated from a common ancestor, whereas the O-antigen modification in E. coli O23, which, most probably, is induced by prophage genes outside the gene cluster, could be introduced after the species divergence.
authors: Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow. perepel@ioc.ac.ru
authors: A V
authors: AV
authors: Perepelov
authors: Bin
authors: B
authors: Liu
authors: Dan
authors: D
authors: Guo
authors: S N
authors: SN
authors: Senchenkova
authors: A S
authors: AS
authors: Shahskov
authors: Lu
authors: L
authors: Feng
authors: Lei
authors: L
authors: Wang
authors: Y A
authors: YA
authors: Knirel
mesh_terms: D002240:Carbohydrate Sequence; D004926:Escherichia coli / Q000737:chemistry / Q000235:genetics / Q000276:immunology*; D008969:Molecular Sequence Data; D005810:Multigene Family; D019906:Nuclear Magnetic Resonance, Biomolecular; D019081:O Antigens / Q000737:chemistry* / Q000235:genetics / Q000276:immunology; D019779:Salmonella enterica / Q000737:chemistry / Q000235:genetics / Q000276:immunology*
chemical_list: D019081:O Antigens; C569667:O-antigen, E coli O23