Structural analysis of the carbohydrate backbone of Vibrio parahaemolyticus O2 lipopolysaccharides.
A structural investigation has been carried out on the carbohydrate backbone of Vibrio parahaemolyticus O2 lipopolysaccharides (LPS) isolated by dephosphorylation, O-deacylation and N-deacylation. The carbohydrate backbone is a short-chain saccharide consisting of nine monosaccharide units i.e., 1 mol each of D-galactose (Gal), D-glucose (Glc), D-glucuronic acid (GlcA), L-glycero-D-manno-heptose (L,D-Hep), D-glycero-D-manno-heptose (D,D-Hep), 3-deoxy-D-manno-oct-2-ulosonic acid (Kdo), 5,7-diacetamido-3,5,7,9-tetradeoxy-D-glycero-D-galacto-non-2-ulosonic acid (NonlA), and 2 mol of 2-amino-2-deoxy-D-glucose (D-glucosamine, GlcN). Based on the data obtained by NMR spectroscopy, fast-atom bombardment mass spectrometry (FABMS) and methylation analysis, a structure was elucidated for the carbohydrate backbone of O2 LPS. In the native O2 LPS, the 2-amino-2-deoxy-D-glucitol (GlcN-ol) at the reducing end of the nonasaccharide is present as GlcN. The lipid A backbone is a beta-D-GlcN-(1-->6)-D-GlcN disaccharide as is the case for many Gram-negative bacterial LPS. The lipid A proximal Kdo is substituted by the distal part of the carbohydrate chain at position-5. In the native O2 LPS, D-galacturonic acid, which is liberated from LPS by mild acid treatment or by dephosphorylation in hydrofluoric acid, is present although its binding position is unknown at present.
Hashii
Noritaka
N
Department of Microbiology School of Pharmaceutical Sciences, Josai University, Sakado, Saitama 350-0295, Japan.
Isshiki
Yasunori
Y
Iguchi
Takehiro
T
Kondo
Seiichi
S
D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D002849:Chromatography, Gas / Q000379:methods; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods; D008070:Lipopolysaccharides / Q000032:analysis / Q000737:chemistry*; D008969:Molecular Sequence Data; D015394:Molecular Structure; D014736:Vibrio parahaemolyticus / Q000737:chemistry*
D008070:Lipopolysaccharides