Cloning and characterization of a Helicobacter bizzozeronii urease gene cluster.
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.
Zhu
Jiaqian
J
Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA.
Teng
Ching-Hao
CH
Chang
Chao-Fu
CF
Chang
Ching-Dong
CD
Simpson
Kenneth W
KW
Wei
Christina
C
McDonough
Patrick
P
McDonough
Sean
S
Chang
Yung-Fu
YF
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
D019151:Peptide Library; D014510:Urease