Cell surface characteristics of Helicobacter pylori

Abstract

Helicobacter pylori is an important gastroduodenal pathogen of humans. Immunological and structural studies have been performed on the phospholipids, lipopolysaccharides (LPS) and some surface proteins of H. pylori strains. H. pylori LPS has, in general, low immunological activity and this property may aid the survival of this chronic infection. Nevertheless, H. pylori LPS has been found to influence the quality of gastric mucin and to stimulate pepsinogen secretion, thereby contributing to gastric disease. A number of putative adhesins of the bacterium have been described. This multiplicity of adhesins may reflect that H. pylori adherence is a multi-step process involving different interactions, and that different adhesins may mediate adherence to various sites in gastric tissue.

Relationship of Blood Group Determinants on Helicobacter pylori Lipopolysaccharide with Host Lewis Phenotype and Inflammatory Response

“…One isolate was identified as having blood group A-like antigen coexpressed with both Le x and Le y , but blood group B antigenic determinant was not identified on any isolate. The presence of blood group antigenic determinants on LPS was confirmed, with a concordance between results of 97%, when proteinase K-treated whole-cell extracts of H. pylori isolates were immunoblotted and high-molecular-weight immunoreactive bands were observed identical to those described previously (15,24). Furthermore, since isolates lacking an O chain would fail to be typeable (15,21), isolates which were nontypeable by both ELISA and immunoblotting were confirmed as possessing an O chain by silver staining of LPS electrophoretic gels (data not shown).…”

“…Like the cell envelopes of other gram-negative bacteria, that of H. pylori contains lipopolysaccharides (LPSs). The low immunological activities of H. pylori LPSs, compared with those of enterobacterial LPSs, have been documented and, by inducing a low response, may prolong H. pylori infection longer than would occur with a more aggressive pathogen (15). The O-specific chain of the LPS of H. pylori has been found to express blood group antigens, predominantly of the type 2 blood group determinants Lewis x (Le x ) and Lewis y (Le y ) (17,21,25).…”

Helicobacter pyloriAugments Growth of Gastric Cancers via the Lipopolysaccharide-Toll-like Receptor 4 Pathway whereas Its Lipopolysaccharide Attenuates Antitumor Activities of Human Mononuclear Cells

“…Lipid A represents the endotoxic principle of active LPS. Lipid A of H. pylori LPS has a unique structure that contains uncommonly long 3-hydroxy fatty acids and a backbone consisting of a D-glucosamine disaccharide with a 2-aminoethylphosphate group at position 1 (35,36). Both H. pylori -and E. coli -derived LPS significantly augmented the proliferation of gastric cancers, and their LPS-induced proliferative activities on cancer cells were almost completely abrogated by neutralizing anti-TLR4 antibodies (Fig.…”

Identification of a d - glycero - d - manno -Heptosyltransferase Gene from Helicobacter pylori

“…3) and O:3::HP0479kan (data not shown) strains, an extended LPS structure with O chain was observed; however, it was noted that the major LPS species in this strain appeared to migrate further into the gel, indicating a reduction in length of the O chain. It is well known that cultures grown on solid media will produce LPS of lower molecular mass (34). In addition, while reactivity with anti-Le Y was restored in the complemented strain (Fig.…”