Molecular characterisation of urease genes from urease-positive thermophilic campylobacters (UPTC)

Abstract

This study aims to clarify the molecular characteristics of the urease gene operon from urease-positive thermophilic campylobacters (UPTC) obtained from different sources and in various countries. Sequence heterogeneity was observed for the promoter structures at the -35-like region among the 12 isolates examined. The most probable TTG start codon was suggested for the ureB and ureH genes, and for the ureA, E, F and G genes, ATG was suggested among all the isolates examined. Overlap was detected between ureA and ureB and between ureB and ureE among all the isolates examined. UPTC is the first example of an overlap between the two structural genes ureA and ureB. When the completely sequenced open reading frames (ORFs) for ureE, ureF, ureG and ureH were identified, non-coding regions between ureE and ureF, ureF and ureG, and ureG and ureH were also demonstrated. All six start codons of the six urease genes were demonstrated to be preceded by Shine-Dalgarno sequences among all the isolates examined. The Cys-His sequence corresponding to urease active sites were aligned perfectly and fully conserved among the three UPTC isolates examined. A putative and intrinsic p-independent transcriptional terminator was identified to be identical among all the isolates examined. A partial and putative ORF of about 200 bp in length showing high sequence similarity to GTP cyclohydrolase I was observed downstream of ureH.

Genome Sequence of Anoxybacillus geothermalis Strain GSsed3, a Novel Thermophilic Endospore-Forming Species

“…GSsed3 was biochemically tested and found to hydrolyze urea and reduce nitrates to nitrites. Genome annotation supports these findings, since it revealed the presence of the loci ureE and ureC for urease activity ( 13 ) and two copies of a putative nitrate reductase. It assimilates mannitol as an alternative carbon source to glucose.…”

Molecular analysis and characterization of a urease gene operon from Campylobacter sputorum biovar paraureolyticus

“…In addition, the second ureasepositive organisms of C. sputorum biovar paraureolyticus among the genus Campylobacter were identified from bovine feces and human diarrhea (On et al 1998). Consequently, our research group has already clarified the molecular characteristics of urease gene operons from both of the two Campylobacter taxa (UPTC CF89-12 and C. sputorum biovar paraureolyticus LMG 17591) in previous (Usui et al 2006;Kakinuma et al 2007;Kakinuma et al 2008) and present studies.…”

Biochemical characterisation of urease from urease-positive thermophilic Campylobacter (UPTC)

“…19,21,22 Therefore, the present study aims to characterise urease biochemically from a Japanese C. lari UPTC isolate (CF89-12).…”