Mutational analysis of the locus of enterocyte effacement-encoded regulator (Ler) of enteropathogenic Escherichia coli.

ABSTRACT: The locus of enterocyte effacement (LEE) pathogenicity island of enterohemorrhagic and enteropathogenic Escherichia coli (EHEC and EPEC, respectively) comprises a cluster of operons encoding a type III secretion system and related proteins, all of which are essential for bacterial colonization of the host intestines. The LEE1 operon encodes Ler, which positively regulates many EPEC and EHEC virulence genes located in the LEE region and elsewhere in the chromosome. In addition, Ler is a specific autorepressor of LEE1 transcription. To better understand the function of Ler, we screened for Ler mutants defective in autorepression. We isolated 18 different point mutations in Ler, rendering it defective in autorepression and in DNA binding. Among these mutants were those defective in positive r

SUBMITTER: Yerushalmi G 

PROVIDER: S-EPMC2583616 | biostudies-literature | 2008 Dec

REPOSITORIES: biostudies-literature