Project description:The human gastric pathogen Helicobacter pylori is extremely well adapted to the highly acidic conditions encountered in the stomach. The pronounced acid resistance of H. pylori relies mainly on the ammonia-producing enzyme urease, however, urease-independent mechanisms are likely to contribute to acid adaptation. Acid-responsive gene regulation is mediated at least in part by the ArsRS two-component system consisting of the essential OmpR-like response regulator ArsR and the non-essential cognate histidine kinase ArsS whose autophosphorylation is triggered in response to low pH. In this study by global transcriptional profiling of an ArsS-deficient H. pylori mutant grown at pH 5.0 we define the ArsR~P- dependent regulon consisting of 110 genes including the urease gene cluster, the genes encoding the aliphatic amidases AmiE and AmiF and the rocF gene encoding arginase. Keywords: Identification of an ArsRS-Regulon
Project description:Helicobacter pylori (H. pylori) is a human pathogen that infects almost half of the world’s population. Infection with H. pylori is frequently associated with chronic gastritis and can even lead to gastric and duodenal ulcers and gastric cancer. Although the persistent colonization of H. pylori and the development of H. pylori-associated gastritis remain poorly understood, it is believed that, in gastric mucosa, the modulated gastric epithelial cells (GECs) by H. pylori are key contributors. We used microarrays to detail the global programme of gene expression in Helicobacter pylori infected-gastric epithelial cell line AGS cells and identified up-regulated genes induced by Helicobacter pylori infection.
Project description:The genome of the gastric pathogen Helicobacter pylori harbors a remarkably low number of regulatory genes, including three and five open reading frames encoding two-component histidine kinases and response regulators, respectively, which are putatively involved in transcriptional regulation. Inactivation of the response regulator gene hp1021 resulted in a severe growth defect, as indicated by a small-colony phenotype. Recently we found that phosphorylation of the receiver domain HP1021 is not needed for its response regulator function and may not occur at all. No target genes have been identified so far. In this study we define the HP1021-dependent regulon consisting of 79 genes (51 activated, 28 repressed) by global transcriptional profiling of an HP1021-deficient H. pylori mutant. Keywords: Identification of an HP1021-Regulon
Project description:Helicobacter pylori infection reprograms host gene expression and influences various cellular processes, which have been investigated by cDNA microarray in vitro culture cells and in vivo patients of the chronic abdominal complaint. In this study,the effects of H. pylori infection on host gene expression in the gastric antral mucosa of patients with chronic gastritis were examined.
Project description:The purpose of this study was to examine macrophage proteomic changes induced by Helicobacter pylori. Macrophages utilized were the RAW 264.7 murine cell line. Macrophages were treated with H. pylori for 24 hours. The experimental design was a 4-plex isobaric tags for relative and absolute quantification (iTRAQ). In addition to uninfected control and H. pylori infected, the additional two conditions included an inhibitor of deoxyhypusine synthase (N1-guanyl-1,7-diamine-heptane, 1-(7-ammonioheptyl)guanidinium sulfate; GC7) an enzyme involved in the hypusination translation pathway, and the inhibitor plus H. pylori.
Project description:Based on preliminary data demonstrating that macrophages are critical regulators of Helicobacter pylori colonization and gastric pathology in mice, we sought to investigate how macrophages may serve as bacterial reservoirs of intracellular H. pylori.
Project description:This SuperSeries is composed of the following subset Series: GSE25146: Changes in gene expression in AGS cells in response to Helicobacter pylori lipopolysaccharide GSE25147: Changes in gene expression in MKN45 cells in response to Helicobacter pylori lipopolysaccharide GSE25148: Changes in gene expression in HEK-TLR2 cells in response to Helicobacter pylori lipopolysaccharide Refer to individual Series
Project description:Differential gene transcript amounts between Helicobacter pylori N6 (wild type strain) bacteria and isogenic tlpD mutant grown in liquid culture to similar O.D.600 (1.0; mid log)