Structural studies on the R-type lipopolysaccharide of Aeromonas hydrophila

A rough strain of Aeromonas hydrophila, AH-901, has an R-type lipopolysaccharide with the complete core. The following core structure was established by chemical degradations followed by sugar and methylation analyses along with ESIMS and NMR spectroscopy:<fig loc="display"><link locator="fx2"></fig>where d-α-d-Hep and l-α-d-Hep stand for d-glycero- and l-glycero-α-d-manno-heptose, respectively; Kdo stands for 3-deoxy-d-manno-oct-2-ulosonic acid; all monosaccharides are in the pyranose form; the degree of substitution with β-d-Gal is ∼50%. Lipid A of the lipopolysaccharide has a 1,4′-bisphosphorylated β-d-GlcN-(1 → 6)-α-d-GlcN disaccharide backbone with both phosphate groups substituted with 4-amino-4-deoxyarabinose residues. [Copyright &y& Elsevier]