Microbiology news and views

J. Mol. Micro. Biotechnol. 4: 367-374

Enhancer-Dependent Transcription in Salmonella enterica Typhimurium: New Members of the sN Regulon Inferred from Protein Sequence Homology and Predicted Promoter Sites

David J. Studholme

DNA-looping mediated by regulatory proteins is a ubiquitous mode of transcriptional control that allows interactions between genetic elements separated over long distances in DNA. In prokaryotes, one of the best-studied examples of regulatory proteins that use DNA-looping is the NtrC family of enhancer-binding proteins (EBPs), which activate transcription from sN- (sigma-N, sigma-54) dependent promoters. The completely sequenced genome of food-borne pathogen Salmonella enterica serovar Typhimurium LT2 contains seven novel EBPs of unknown function. Four of these EBPs have a similar domain organisation to NtrC whilst surprisingly the remaining three resemble LevR in Bacillus subtilis. Probable transcriptional targets are identified for each of the EBPs, including novel homologues of phosphotransferase system Enzyme II (EII) and several virulenceassociated functions. Comparisons are made with the related enteric bacteria Salmonella Typhi, Escherichia coli and Yersinia pestis.-

Full article [pdf]


Copyright © 2002 Horizon Scientific Press. All Rights Reserved.

New and forthcoming molecular biology books

Recommended Reading