Lipopolysaccharide structures of Helicobacter pylori wild-type strain 26695 and 26695 HP0826::Kan mutant devoid of the O-chain polysaccharide component Original Research Article

We describe a re-investigation of the structure of the lipopolysaccharide (LPS) from Helicobacter pylori genomic strain 26695 and its corresponding HP0826::Kan mutant lacking the O-chain component based on the in-depth NMR analysis of the oligosaccharide products obtained through the use of various degradation procedures performed on the purified LPS from both strains, as well as CE–MS data. New structural evidence indicates the presence of the linear arrangement of glucan and heptan portions of the LPS attached through -6-α-ddHep-3-α-l-Fuc-3-β-GlcNAc- fragment to the inner core dd-heptose residue. This structure differs from previously reported structures of the H. pylori 26695 LPS in several aspects.