Cloning, sequencing and characterization of a urease gene operon from urease-positive thermophilic Campylobacter (UPTC).
OBJECTIVE
To clone, sequence and characterize the genetic organization of urease genes within urease-positive thermophilic Campylobacter (UPTC).


RESULTS
An approx. 5.1-kbp region encoding a urease gene operon was identified, when recombinant plasmid DNAs from a genomic DNA library of a Japanese isolate (CF89-12) of UPTC were analysed.


CONCLUSIONS
Six closely spaced and putative open reading frames (ORFs) for ureA, ureB, ureE, ureF, ureG and ureH were detected. ATG codons initiated each ORF of the UPTC urease operon except for ureB and ureH, which commenced with the most probable TTG codon. Overlaps were detected between ureA and ureB and also between ureB and ureE. Probable ribosome-binding sites and a putative rho-independent transcriptional termination region were identified. Two putative promoter structures, consisting of consensus sequences at the -35 like and -10 regions were also identified.


CONCLUSIONS
Construction of a neighbour-joining tree based on the nucleotide sequence data of urease genes indicated that UPTC formed a cluster with some Helicobacter organisms separate from the other urease-producing bacteria, suggesting a commonly shared ancestry between UPTC and Helicobacter urease genes.
Kakinuma
Y
Y
Laboratory of Molecular Biology, School of Environmental Health Sciences, Azabu University, Sagamihara, Japan.
Iida
H
H
Sekizuka
T
T
Usui
K
K
Murayama
O
O
Takamiya
S
S
Millar
B C
BC
Moore
J E
JE
Matsuda
M
M
D000595:Amino Acid Sequence; D001483:Base Sequence; D002167:Campylobacter / Q000201:enzymology / Q000235:genetics*; D003001:Cloning, Molecular; D004269:DNA, Bacterial / Q000235:genetics; D015723:Gene Library; D005798:Genes, Bacterial; D016998:Helicobacter / Q000201:enzymology / Q000235:genetics; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D010802:Phylogeny; D014510:Urease / Q000235:genetics*
D004269:DNA, Bacterial; D014510:Urease