Comparative Genomics ofHelicobacter pylori: Analysis of the Outer Membrane Protein Families

Abstract

The two complete genomic sequences of Helicobacter pylori J99 and 26695 were used to compare the paralogous families (related genes within one genome, likely to have related function) of genes predicted to encode outer membrane proteins which were present in each strain. We identified five paralogous gene families ranging in size from 3 to 33 members; two of these families contained members specific for either H. pylori J99 or H. pylori 26695. Most orthologous protein pairs (equivalent genes between two genomes, same function) shared considerable identity between the two strains. The unusual set of outer membrane proteins and the specialized outer membrane may be a reflection of the adaptation of H. pylori to the unique gastric environment where it is found. One subfamily of proteins, which contains both channel-forming and adhesin molecules, is extremely highly related at the sequence level and has likely arisen due to ancestral gene duplication. In addition, the largest paralogous family contained two essentially identical pairs of genes in both strains. The presence and genomic organization of these two pairs of duplicated genes were analyzed in a panel of independent H. pylori isolates. While one pair was present in every strain examined, one allele of the other pair appeared partially deleted in several isolates.

Investigation of Association between oipA and iceA1/iceA2 Genotypes of Helicobacter pylori and Gastric Cancer in Iran

“…OipA, also known as HopH, is a member of outer membrane proteins (OMPs) family 1 that is encoded by HP0638/hopH gene of H pylori (Alm et al, 2000). OipA is shown to be associated with increased secretion of interleukin 8, progression of gastric inflammation, bacterial adherence and adaptation to the host microenvironment (Yamaoka et al, 2000;2002;Dossumbekova et al, 2006), and thereby, contribute to development of gastroentric diseases.…”

The Three-dimensional Structure of the Extracellular Adhesion Domain of the Sialic Acid-binding Adhesin SabA from Helicobacter pylori

“…The molecular mechanisms underpinning the various functions of SabA protein therefore remain unknown. Currently, however, it is predicted that the extracellular adhesin domain of SabA contains key determinants for interaction with the host cell surface (9). Accordingly, to investigate the structural basis of SabA adhesin function and furthermore to provide structural insights across the SabA/BabA superfamily, we set out to determine the three-dimensional structure of the soluble SabA adhesin domain.…”

Birth and death of genes linked to chromosomal inversion

“…1A; for details, see Genome Comparison in Materials and Methods and SI Materials and Methods). These changes may have contributed to host adaptation because OMPs in general, and these OMP families in particular, are important in host interaction and pathogenicity (9)(10)(11).…”