title: Cloning and characterization of a Helicobacter bizzozeronii urease gene cluster.
abstract: The urease gene cluster from Helicobacter bizzozeronii was cloned and sequenced. A genomic library was constructed in a lambda-ZAPII vector using TSP5091-digested H. bizzozeronii chromosomal DNA. Four overlapping recombinant bacteriophages carrying the H. bizzozeronii urease genes were identified by using a fragment of H. bizzozeronii ureB as a probe. Sequence analysis of two clones (pHB1 and pHB3) revealed seven open reading frames encoding proteins with predicted masses of 26.5, 60.3, 21.7, 19.5, 28.6, 21.7 and 29.6 kDa representing the structural genes, Urease A and B and its accessory genes, urease I, E, F, G and H, respectively. In addition, three open reading frames upstream of the ureA gene encoding a putative tRNA transferase, a putative Glucose inhibited division protein B (GidB) and a protein with unknown function were also identified. A clone (pHB5) containing a complete urease gene cluster was constructed. The homologue analysis revealed that UreA polypeptide exhibited 64-90% identity to that of Helicobacter heilmanii, Helicobacter felis, Helicobacter pylori, Helicobacter mustelae and Helicobacter hepaticus. UreB polypeptides exhibited 76.8-96% identity to that of H. heilmanii, H. felis, H. pylori, H. mustelae and H. hepaticus. The UreI, E, F, G and H also showed 44-86% identity to that of H. pylori. Among these accessory genes, UreE had a lowest percentage identity to that of H. pylori.
authors.affiliation: Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA.
authors.forename: Jiaqian
authors.initials: J
authors.lastname: Zhu
authors.forename: Ching-Hao
authors.initials: CH
authors.lastname: Teng
authors.forename: Chao-Fu
authors.initials: CF
authors.lastname: Chang
authors.forename: Ching-Dong
authors.initials: CD
authors.lastname: Chang
authors.forename: Kenneth W
authors.initials: KW
authors.lastname: Simpson
authors.forename: Christina
authors.initials: C
authors.lastname: Wei
authors.forename: Patrick
authors.initials: P
authors.lastname: McDonough
authors.forename: Sean
authors.initials: S
authors.lastname: McDonough
authors.forename: Yung-Fu
authors.initials: YF
authors.lastname: Chang
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D015153:Blotting, Western; D003001:Cloning, Molecular; D016998:Helicobacter / Q000235:genetics* / Q000378:metabolism; D008969:Molecular Sequence Data; D005810:Multigene Family; D019151:Peptide Library; D014510:Urease / Q000235:genetics* / Q000378:metabolism
chemical_list: D019151:Peptide Library; D014510:Urease