Development of inducible systems to engineer conditional mutants of essential genes of Helicobacter pylori.

ABSTRACT: The Escherichia coli-Helicobacter pylori shuttle vector pHeL2 was modified to introduce the inducible LacI(q)-pTac system of E. coli, in which the promoters were engineered to be under the control of H. pylori RNA polymerase. The amiE gene promoter of H. pylori was taken to constitutively express the LacI(q) repressor. Expression of the reporter gene lacZ was driven by either pTac (pILL2150) or a modified version of the ureI gene promoter in which one or two LacI-binding sites and/or mutated nucleotides between the ribosomal binding site and the ATG start codon (pILL2153 and pILL2157) were introduced. Promoter activity was evaluated by measuring beta-galactosidase activity. pILL2150 is a tightly regulated expression system suitable for the analysis of genes with low-level expression, while

SUBMITTER: Boneca IG 

PROVIDER: S-EPMC2292604 | biostudies-literature | 2008 Apr

REPOSITORIES: biostudies-literature