The cyclic AMP-cyclic AMP receptor protein complex regulates activity of the traJ promoter of the Escherichia coli conjugative plasmid pRK100.

ABSTRACT: The TraJ protein is a central activator of F-like plasmid conjugal transfer. In a search for regulators of traJ expression, we studied the possible regulatory role of the cyclic AMP (cAMP)-cAMP receptor protein (CRP) complex in traJ transcription using a traJ-lacZ reporter system. A comparison of the enzyme activities in the wild-type Escherichia coli strain MC4100 with those in cya and crp mutants indicated that disruption of the formation of the cAMP-CRP complex negatively influenced the activity of the traJ promoter of the F-like plasmid pRK100. The defect in the cya mutant was partially restored by addition of exogenous cAMP. Competitive reverse transcription-PCR performed with RNA isolated from the wild-type and mutant strains showed that the cAMP-CRP complex exerted its effect at the

SUBMITTER: Starcic M 

PROVIDER: S-EPMC148056 | biostudies-literature | 2003 Mar

REPOSITORIES: biostudies-literature