Transcriptional control of toxT, a regulatory gene in the ToxR regulon of Vibrio cholerae
- 27 October 1994
- journal article
- Published by Wiley in Molecular Microbiology
- Vol. 14 (1) , 17-29
Abstract
Summary: Co‐ordinate expression of many virulence genes in Vibrio cholerae is under the control of the ToxR and ToxT proteins. These proteins function in a regulatory cascade in which ToxR is required to activate toxT, and ToxT activates virulence genes. The precise mechanism for ToxR activation of toxT is unknown, but data presented in this report suggest a direct involvement of ToxR. Primer extension and gene fusion analyses identified a ToxR‐regulated promoter directly upstream of toxT, immediately following a region of inverted repeats capable of terminating transcription. Gel mobility shift studies indicate that ToxR binds DNA within the inverted repeat region, yet preliminary evidence suggests that ToxR binding alone is not sufficient for activation of toxT. Possible mechanisms of ToxR‐dependent toxT expression are discussed.Keywords
This publication has 33 references indexed in Scilit:
- Co‐ordinate expression of virulence genes by ToxR in Vibrio choleraeMolecular Microbiology, 1992
- Functional Importance of Sequence in the Stem-Loop of a Transcription TerminatorScience, 1991
- Type 1 fimbriae mutants of Escherichia coli K12: characterization of recognized afimbriate strains and construction of new fim deletion mutantsMolecular Microbiology, 1991
- DNA supercoiling and environmental regulation of virulence gene expression in Shigella flexneriNature, 1990
- Toxin, toxin-coregulated pili, and the toxR regulon are essential for Vibrio cholerae pathogenesis in humans.Journal of Experimental Medicine, 1988
- The heat shock response of E. coli is regulated by changes in the concentration of σ32Nature, 1987
- Cholera toxin transcriptional activator ToxR is a transmembrane DNA binding proteinCell, 1987
- POSITIVE CONTROL OF TRANSCRIPTION INITIATION IN BACTERIAAnnual Review of Genetics, 1984
- Cholera toxin genes: nucleotide sequence, deletion analysis and vaccine developmentNature, 1983
- Modulation of the two promoters of the galactose operon of Escherichia coliNature, 1979