title: Structural studies of the side chain of outer membrane lipopolysaccharide from Pseudomonas syringae pv. coriandricola W-43.
abstract: The lipopolysaccharide (LPS) was isolated from Pseudomonas syringae pv. coriandricola W-43 by hot phenol-water extraction. Rhamnose and 3-N-acetyl-3-deoxyfucose were found to be the major sugar constituents of the LPS together with N-acetylglucosamine, N-acetylgalactosamine, heptose, and 3-deoxy-D-manno-octulosonic acid (Kdo). The main fatty acids of lipid A of the LPS were 3-OH-C:10, C12:0, 2-OH-C12:0, and 3-OH-C12:0. The O-specific polysaccharide liberated from the LPS by mild-acid hydrolysis was purified by gel permeation chromatography. The compositional analysis of the O-specific polysaccharide revealed the presence of L-rhamnose and 3-N-acetyl-3-deoxy-D-fucose in a molar ratio of 4:1. The primary structure of the O-specific polysaccharide was established by methylation analysis together with 1H and 13C nuclear magnetic resonance spectroscopy, including two-dimensional shift-correlated and one-dimensional nuclear Overhauser effect spectroscopy. The polysaccharide moiety was found to consist of a tetrasaccharide rhamnan backbone, and 3-N-acetyl-3-deoxy-D-fucose constitutes the side chain of the branched pentasaccharide repeating unit of the polysaccharide.
authors.affiliation: Department of Biological Chemistry, Indian Association for the Cultivation of Science, Jadavpur, Calcutta.
authors.forename: S
authors.initials: S
authors.lastname: Das
authors.forename: M
authors.initials: M
authors.lastname: Ramm
authors.forename: H
authors.initials: H
authors.lastname: Kochanowski
authors.forename: S
authors.initials: S
authors.lastname: Basu
mesh_terms: D002240:Carbohydrate Sequence; D002462:Cell Membrane / Q000737:chemistry* / Q000276:immunology; D005227:Fatty Acids / Q000032:analysis; D005643:Fucose / Q000031:analogs & derivatives / Q000032:analysis; D008070:Lipopolysaccharides / Q000737:chemistry* / Q000276:immunology; D009682:Magnetic Resonance Spectroscopy; D008745:Methylation; D008969:Molecular Sequence Data; D019081:O Antigens; D011135:Polysaccharides, Bacterial / Q000737:chemistry*; D011549:Pseudomonas / Q000737:chemistry* / Q000276:immunology; D012210:Rhamnose / Q000032:analysis
chemical_list: C090110:3-N-acetyl-3-deoxyfucose; D005227:Fatty Acids; D008070:Lipopolysaccharides; D019081:O Antigens; D011135:Polysaccharides, Bacterial; D005643:Fucose; D012210:Rhamnose