Regulation of the AcrAB multidrug efflux pump in Salmonella enterica serovar Typhimurium in response to indole and paraquat.

摘要: Salmonella enterica serovar Typhimurium has at least nine multidrug efflux pumps. Among these, AcrAB is constitutively expressed and the most efficient, playing a role in both drug resistance virulence. The acrAB locus induced by indole, Escherichia coli-conditioned medium, bile salts. This induction dependent on RamA through binding sequence upstream region of acrA that binds RamA. In present study, we made detailed investigation ramA mechanisms response to biological oxidant for bacteria. We found indole RamR. However, cysteine residues RamR do not play oxidative effect therefore related via Furthermore, showed paraquat, superoxide generator, induces but ramA. further discovered mechanism paraquat SoxS. data indicate there are two independent pathways extracellular signals such as paraquat. propose utilizes these regulators order adapt itself environmental conditions.