title: Lipopolysaccharides possessing two L-glycero-D-manno-heptopyranosyl-alpha -(1-->5)-3-deoxy-D-manno-oct-2-ulopyranosonic acid moieties in the core region. The structure of the core region of the lipopolysaccharides from Burkholderia caryophylli.
abstract: The carbohydrate backbone of the core-lipid A region was characterized from the lipopolysaccharides (LPSs) of the plant-pathogenic bacterium Burkholderia caryophylli. For the first time, the presence of two moieties of l-glycero-d-manno-heptopyranosyl-alpha-(1-->5)-3-deoxy-d-manno-oct-2-ulopyranosonic acid was identified in a core region, which is of particular interest with regard to the biosynthesis of this and of LPSs in general. The LPSs of B. caryophylli were degraded by mild hydrazinolysis (de-O-acylation), treatment with 48% aqueous HF at 4 degrees C (cleavage of phosphate groups and destruction of the O-specific polysaccharides), reduction with NaBH4, and de-N-acylation utilizing hot KOH. The major oligosaccharide representing the carbohydrate backbone of the core region and lipid A was isolated by high-performance anion-exchange chromatography. Its analysis employing compositional and methylation analyses, matrix-assisted laser desorption/ionization mass spectrometry, and (1)H and (13)C NMR spectroscopy applying various one-dimensional and two-dimensional experiments identified the following structure. Structure I All sugars are pyranoses and alpha-linked, if not stated otherwise. Hep is l-glycero-d-manno-heptose, Kdo is 3-deoxy-d-manno-oct-2-ulosonic acid.
authors.affiliation: Dipartimento di Chimica Organica e Biochimica, Università degli studi di Napoli "Federico 11," I-80126 Napoli, Italy.
authors.forename: Antonio
authors.initials: A
authors.lastname: Molinaro
authors.forename: Cristina
authors.initials: C
authors.lastname: De Castro
authors.forename: Rosa
authors.initials: R
authors.lastname: Lanzetta
authors.forename: Antonio
authors.initials: A
authors.lastname: Evidente
authors.forename: Michelangelo
authors.initials: M
authors.lastname: Parrilli
authors.forename: Otto
authors.initials: O
authors.lastname: Holst
mesh_terms: D019117:Burkholderia / Q000737:chemistry*; D002240:Carbohydrate Sequence; D008070:Lipopolysaccharides / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D008745:Methylation; D008969:Molecular Sequence Data; D009844:Oligosaccharides / Q000737:chemistry; D013400:Sugar Acids / Q000737:chemistry* / Q000378:metabolism*
chemical_list: D008070:Lipopolysaccharides; D009844:Oligosaccharides; D013400:Sugar Acids