title: Identification of target genes regulated by the two-component system HP166-HP165 of Helicobacter pylori.
abstract: Two-component systems are signal transduction systems which enable bacteria to regulate cellular functions in response to changing environmental conditions. In most cases regulation is accomplished on the transcriptional level by a response regulator protein, which, according to the phosphorylation state of its receiver domain, displays different affinities for its target promoters. Here we describe identification of genes regulated by the two-component system HP166-HP165 of Helicobacter pylori and characterization of the corresponding target promoters. We demonstrated that expression of the HP166-HP165 two-component system is negatively autoregulated under conditions favoring autophosphorylation of the histidine kinase. Furthermore, we found that response regulator HP166 activates transcription of genes encoding a protein family with an unknown function present in H. pylori 26695, as well as an operon composed of five H. pylori-specific genes. While open reading frame HP166 is an essential gene, the target genes of the response regulator are not required for growth under in vitro culture conditions.
authors.affiliation: Theodor-Boveri-Institut für Biowissenschaften, Lehrstuhl für Mikrobiologie, Universität Würzburg, Am Hubland, D-97074 Würzburg, Germany.
authors.forename: Patricia
authors.initials: P
authors.lastname: Dietz
authors.forename: Gabriele
authors.initials: G
authors.lastname: Gerlach
authors.forename: Dagmar
authors.initials: D
authors.lastname: Beier
mesh_terms: D001483:Base Sequence; D001665:Binding Sites; D004269:DNA, Bacterial; D015964:Gene Expression Regulation, Bacterial; D015971:Gene Expression Regulation, Enzymologic; D005798:Genes, Bacterial; D016480:Helicobacter pylori / Q000201:enzymology / Q000235:genetics* / Q000254:growth & development; D000071677:Histidine Kinase; D006706:Homeostasis; D006801:Humans; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D011401:Promoter Regions, Genetic; D011494:Protein Kinases / Q000235:genetics* / Q000378:metabolism; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism*; D012689:Sequence Homology, Nucleic Acid; D015534:Trans-Activators / Q000235:genetics / Q000378:metabolism*
chemical_list: D004269:DNA, Bacterial; D012097:Repressor Proteins; D015534:Trans-Activators; D011494:Protein Kinases; D000071677:Histidine Kinase