title: The histone-like protein HU has a role in gene expression during the acid adaptation response in Helicobacter pylori.
abstract: BACKGROUND
  Gastritis, ulcers, and gastric malignancy have been linked to human gastric epithelial colonization by Helicobacter pylori. Characterization of the mechanisms by which H. pylori adapts to the human stomach environment is of crucial importance to understand H. pylori pathogenesis.
  
  
  METHODS
  In an effort to extend our knowledge of these mechanisms, we used proteomic analysis and qRT-PCR to characterize the role of the histone-like protein HU in the response of H. pylori to low pH.
  
  
  RESULTS
  Proteomic analysis revealed that genes involved in chemotaxis, oxidative stress, or metabolism are under control of the HU protein. Also, expression of the virulence factors Ggt and NapA is affected by the null mutation of hup gene both at neutral and acid pH, as evidenced by qRT-PCR analysis.
  
  
  CONCLUSIONS
  Those results showed that H. pylori gene expression is altered by shift to low pH, thus confirming that acid exposure leads to profound changes in genomic expression, and suggest that the HU protein is a regulator that may help the bacterium adapt to the acid stress. In accordance with previous reports, we found that the HU protein participates in gene expression regulation when the microorganism is exposed to acid stress. Such transcriptional regulation underlies protein accumulation in the H. pylori cell.
authors.affiliation: Laboratory of Molecular Microbiology, Department of Molecular and Cellular Biology, Faculty of Medicine, ICBM, University of Chile, Santiago, Chile.
authors.forename: Alhejandra
authors.initials: A
authors.lastname: Álvarez
authors.affiliation: Laboratory of Molecular Microbiology, Department of Molecular and Cellular Biology, Faculty of Medicine, ICBM, University of Chile, Santiago, Chile.
authors.forename: Héctor
authors.identifier: http://orcid.org/0000-0001-8813-2873
authors.initials: H
authors.lastname: Toledo
mesh_terms: D000222:Adaptation, Physiological; D001426:Bacterial Proteins / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000378:metabolism*; D005744:Gastric Acid; D020869:Gene Expression Profiling; D015964:Gene Expression Regulation, Bacterial; D016480:Helicobacter pylori / Q000187:drug effects* / Q000502:physiology*; D006801:Humans; D020543:Proteome / Q000032:analysis; D040901:Proteomics; D060888:Real-Time Polymerase Chain Reaction
chemical_list: D001426:Bacterial Proteins; D004268:DNA-Binding Proteins; D020543:Proteome; C040330:histone-like protein HU, bacteria
keywords: 
  Helicobacter pylori
  ; acid stress; histone-like protein HU