Gene Activation through the Modulation of Nucleoid Structures by a Horizontally Transferred Regulator, Pch, in Enterohemorrhagic Escherichia coli.

ABSTRACT: The horizontally transferred chromosomal segments, which are the main source of genetic diversity among bacterial pathogens, are bound by the nucleoid protein H-NS, resulting in the formation of a nucleoprotein complex and the silencing of gene expression. The de-silencing or activation of virulence genes necessary for the colonization of enterohemorrhagic Escherichia coli is achieved mainly by the action of two regulators, Pch and Ler, which are encoded by horizontally transferred elements. Although Ler has been shown to activate transcription by counteracting H-NS silencing, the mechanism for Pch is poorly understood. We show here that Pch activates the LEE1 promoter and also enhances the Ler-mediated activation of other LEE promoters. Transcriptional activation was completely dependent

SUBMITTER: Fukui N 

PROVIDER: S-EPMC4764244 | biostudies-literature | 2016

REPOSITORIES: biostudies-literature