The Roles of Escherichia coli cyaA / crp Genes in Metal Stress

Abstract

Adenosine 3 ′, 5′-monophosphate (cAMP) is an important signaling molecule. CRP, the receptor protein of cAMP, acts as the 'main' regulator for transcription factors. The CRP-cAMP complex directly controls at least 500 promoters in Escherichia coli. In this study, the roles of cyaA and crp genes in E. coli BW25113 strain under metal stress were investigated. The minimal inhibition concentration (MIC) and minimal cidal concentration (MCC) of 5 different metals (Zn, Ni, Co, Cd and Cu) on Escherichia coli BW25113 wild type, cyaA and crp mutant cells were determined. In addition, the effect of these metals on the survival of E. coli cyaA / crp mutants was determined by growth and drop plate method. According to E. coli BW25113 wild type, cyaA mutant strain was observed sensitivity in all metals except copper, whereas resistance was observed in crp mutant strain only to zinc metal. The roles of the cyaA and crp genes in metal stress were confirmed by completing the genes on the plasmid. As a result, the roles of cyaA and crp genes in metal resistance were revealed in this study.