Somatic antigens of pseudomonads: structure of the O-specific polysaccharide of Pseudomonas fluorescens IMV 2366 (biovar C)

Structure of the O-specific polysaccharide of Ochrobactrum endophyticum KCTC 42485T containing 3-(3-hydroxy-2,3-dimethyl-5-oxoprolyl)amino-3,6-dideoxy-d-galactose

Ochrobactrum endophyticum (syn. Brucella endophytica) is an aerobic species of Alphaproteobacteria isolated from healthy roots of Glycyrrhiza uralensis. Here we report the structure of the O-specific polysaccharide obtained by mild acid hydrolysis of the lipopolysaccharide of the type strain KCTC 42485:→3)-α-l-FucpNAc-(1→3)-β-d-QuipNAc-(1→2)-β-d-Fucp3NAcyl-(1→ where Acyl is 3-hydroxy-2,3-dimethyl-5-oxoprolyl. The structure was elucidated using chemical analyses along with ¹H and ¹³C NMR spectroscopy (including ¹H,¹H COSY, TOCSY, ROESY and ¹H,¹³C HSQC, HMBC, HSQC-TOCSY and HSQC-NOESY experiments). To our knowledge the OPS structure is novel and has not been previously published.

Structural analysis of the O-specific polysaccharide from the lipopolysaccharide of Aeromonas veronii bv. sobria strain K49

The O-specific polysaccharide obtained by mild-acid degradation of the lipopolysaccharide from Aeromonas veronii bv. sobria strain K49 was studied by sugar and methylation analyses along with (1)H and (13)C NMR spectroscopy. The sequence of the sugar residues was determined using (1)H,(1)H NOESY and (1)H,(13)C HMBC experiments. The O-specific polysaccharide was found to be a high molecular mass polysaccharide composed of repeating units of the structure: →2)-β-D-Quip3NAc-(1→3)-α-L-Rhap-(1→3)-α-L-Rhap-(1→2)-α-L-Rhap-(1→3)-α-D-FucpNAc-(1→ ESI MS confirmed the pentasaccharide structure of the repeating unit, as the molecular mass peaks seen in the spectrum differed by 812.34 u, a value corresponding to the calculated molecular mass of the O-unit.

Structure of the major O-specific polysaccharide from the lipopolysaccharide of Pseudomonas fluorescens BIM B-582: identification of 4-deoxy-D-xylo-hexose as a component of bacterial polysaccharides

A novel constituent of bacterial polysaccharides, 4-deoxy-D-xylo-hexose (D-4dxylHex), was found in the major O-specific polysaccharide from the lipopolysaccharide of Pseudomonas fluorescens BIM B-582. D-4dxylHex was isolated in the free state by paper chromatography after full acid hydrolysis of the polysaccharide and identified by GLC-mass spectrometry, 1H and 13C NMR spectroscopy, and specific rotation. It occurs as a lateral substituent in ∼40% of the oligosaccharide repeating units, making the polysaccharide devoid of strict regularity. The structure of the polysaccharide was established by sugar analysis, Smith degradation, and two-dimensional 1H and 13C NMR spectroscopy. In addition, a minor polysaccharide was isolated from the same lipopolysaccharide and found to contain 4-O-methylrhamnose.

Structural elucidation of a novel core oligosaccharide backbone of the lipopolysaccharide from the new bacterial species Agrobacterium larrymoorei

Agrobacterium larrymoorei is a Gram-negative phytopathogenic bacterium, which produces tumours on Ficus benjamina plants and differs from other Agrobacteria both genetically and biochemically. The lipopolysaccharide (LPS) plays an important role in the pathogenesis of Agrobacteria. The present paper is the first report on the molecular primary structure of the core region of an Agrobacterium LPS. The following structure of the core and lipid A carbohydrate backbone of an R-form LPS of A. larrymoorei was determined by chemical degradations and 1D and 2D NMR spectroscopy: [carbohydrate structure: see text] All sugars are alpha-D-pyranoses if not stated otherwise, Kdo is 3-deoxy-D-manno-oct-2-ulosonic acid, Qui3NAcyl is 3,6-dideoxy-3-(3-hydroxy-2,3-dimethyl-5-oxoprolylamino)glucose, GlcAN and GalAN are amides of GlcA and GalA.