title: Molecular identification and characterisation of catalase and catalase-like protein genes in urease-positive thermophilic Campylobacter (UPTC).
abstract: BACKGROUND
  Thermophilic Campylobacter are important bacterial pathogens of foodborne diseases worldwide. These organisms' physiology requires a microaerophilic atmosphere. To date, little is known about the protective catalase mechanism in urease-positive thermophilic campylobacters (UPTC); hence, it was the aim of this study to identify and characterise catalase and catalase-like protein genes in these organisms.
  
  
  METHODS
  Catalase (katA) and catalase (Kat)-like protein genes from the Japanese UPTC CF89-12 strain were molecularly analysed and compared with C. lari RM2100 and other C. lari and thermophilic Campylobacter reference isolates.
  
  
  RESULTS
  A possible open reading frame of 1,422 base pairs, predicted to encode a peptide of 474 amino acid residues, with calculated molecular weight of 52.7 kilo Daltons for katA, was identified within UPTC CF89-12. A probable ribosome binding site, two putative promoters and a putative ρ-independent transcription terminator were also identified within katA. A similar katA cluster also existed in the C. lari RM2100 strain, except that this strain carries no DcuB genes. However, the Kat-like protein gene or any other homologue(s) were never identified in the C. lari RM2100 strain, or in C. jejuni and C. upsaliensis.
  
  
  CONCLUSIONS
  This study demonstrates the presence of catalase/catalase-like protein genes in UPTC organisms. These findings are significant in that they suggest that UPTC organisms have the protective genetic capability of helping protect the organisms from toxic oxygen stress, which may help them to survive in physiologically harsh environments, both within human and animal hosts, as well as in the natural environment.
authors.affiliation: a Laboratory of Molecular Biology, Graduate School of Environmental Health Sciences , Azabu University , Sagamihara , Japan.
authors.forename: T
authors.initials: T
authors.lastname: Nakajima
authors.affiliation: a Laboratory of Molecular Biology, Graduate School of Environmental Health Sciences , Azabu University , Sagamihara , Japan.
authors.forename: T
authors.initials: T
authors.lastname: Kuribayashi
authors.affiliation: b Northern Ireland Public Health Laboratory, Department of Bacteriology , Belfast City Hospital , Belfast, Northern Ireland , UK.|c School of Biomedical Sciences , University of Ulster , Coleraine, Co. Londonderry , Northern Ireland , UK.|d Centre for Infection and Immunity, Queen's University , Belfast , Northern Ireland , UK.
authors.forename: J E
authors.initials: JE
authors.lastname: Moore
authors.affiliation: b Northern Ireland Public Health Laboratory, Department of Bacteriology , Belfast City Hospital , Belfast, Northern Ireland , UK.
authors.forename: B C
authors.initials: BC
authors.lastname: Millar
authors.affiliation: a Laboratory of Molecular Biology, Graduate School of Environmental Health Sciences , Azabu University , Sagamihara , Japan.
authors.forename: S
authors.initials: S
authors.lastname: Yamamoto
authors.affiliation: a Laboratory of Molecular Biology, Graduate School of Environmental Health Sciences , Azabu University , Sagamihara , Japan.
authors.forename: Motoo
authors.initials: M
authors.lastname: Matsuda
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D001665:Binding Sites; D002167:Campylobacter / Q000145:classification* / Q000201:enzymology* / Q000302:isolation & purification; D002374:Catalase / Q000737:chemistry* / Q000235:genetics*; D004789:Enzyme Activation; D008970:Molecular Weight; D011485:Protein Binding; D011487:Protein Conformation; D013045:Species Specificity; D014510:Urease / Q000378:metabolism*
chemical_list: D002374:Catalase; D014510:Urease
keywords: Thermophilic Campylobacter; UPTC; catalase and catalase-like genes; oxidative stress defence