Bacteriophage Transcription Factor Cro Regulates Virulence Gene Expression in Enterohemorrhagic Escherichia coli.

ABSTRACT: Bacteriophage-encoded genetic elements control bacterial biological functions. Enterohemorrhagic Escherichia coli (EHEC) strains harbor lambda-phages encoding the Shiga-toxin (Stx), which is expressed during the phage lytic cycle and associated with exacerbated disease. Phages also reside dormant within bacterial chromosomes through their lysogenic cycle, but how this impacts EHEC virulence remains unknown. We find that during lysogeny the phage transcription factor Cro activates the EHEC type III secretion system (T3SS). EHEC lambdoid phages are lysogenic under anaerobic conditions when Cro binds to and activates the promoters of T3SS genes. Interestingly, the Cro sequence varies among phages carried by different EHEC outbreak strains, and these changes affect Cro-dependent T3SS regulatio

SUBMITTER: Hernandez-Doria JD 

PROVIDER: S-EPMC5982111 | biostudies-literature | 2018 May

REPOSITORIES: biostudies-literature