title: Structure of the oligosaccharide chain of the SR-type lipopolysaccharide of Ralstonia solanacearum Toudk-2.
abstract: Aiming at improving classification and taxonomy of Gram-negative phytopathogenic bacteria, we studied the structure of the lipopolysaccharide of Ralstonia solanacearum. Mild acid hydrolysis of the lipopolysaccharide of strain Toudk-2 followed by gel chromatography resulted in an O-polysaccharide and two oligosaccharide fractions. The smallest-size oligosaccharide fraction was studied by sugar analysis, high-resolution electrospray ionization mass spectrometry, and, after fractionation by anion-exchange chromatography on HiTrap Q, by one- and two-dimensional (1)H and (13)C NMR spectroscopy. It was found that the isolated oligosaccharides consist of the lipopolysaccharide core with one O-polysaccharide repeat (O-unit) attached. The core exists in two major glycoforms differing from each other in a lateral octulosonic acid residue, which is either D-glycero-D-talo-oct-2-ulosonic acid or 3-deoxy-D-manno-oct-2-ulosonic acid. A peculiar feature of the core is the occurrence of 4-amino-4-deoxy-L-arabinose nonstoichiometrically linked to a heptose residue. The full structures of the core and the biological O-unit as well as the site of the attachment of the O-unit to the core were established.
authors.affiliation: ND Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, 119991 Moscow, Russia. evelina@ioc.ac.ru
authors.forename: Evelina L
authors.initials: EL
authors.lastname: Zdorovenko
authors.forename: Evgeny
authors.initials: E
authors.lastname: Vinogradov
authors.forename: Kerstin
authors.initials: K
authors.lastname: Wydra
authors.forename: Buko
authors.initials: B
authors.lastname: Lindner
authors.forename: Yuriy A
authors.initials: YA
authors.lastname: Knirel
mesh_terms: D002850:Chromatography, Gel / Q000379:methods; D002852:Chromatography, Ion Exchange / Q000379:methods; D005583:Fourier Analysis; D006868:Hydrolysis; D007477:Ions; D008070:Lipopolysaccharides / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D008956:Models, Chemical; D019081:O Antigens / Q000737:chemistry; D009844:Oligosaccharides / Q000737:chemistry*; D011135:Polysaccharides, Bacterial / Q000737:chemistry; D043368:Ralstonia solanacearum / Q000378:metabolism*; D021241:Spectrometry, Mass, Electrospray Ionization
chemical_list: D007477:Ions; D008070:Lipopolysaccharides; D019081:O Antigens; D009844:Oligosaccharides; D011135:Polysaccharides, Bacterial