Two routes of MexS‐MexT‐mediated regulation of MexEF‐OprN and MexAB‐O…

The NfxC‐type mutant of Pseudomonas aeruginosa produces the MexEF‐OprN efflux pump and downregulates expression of the quorum‐sensing‐dependent efflux pump MexAB‐OprM and production of virulence factors in the presence of an active transcriptional regulator, MexT. Consequently, these cells are resistant to chloramphenicol and hypersusceptible to b‐lactam antibiotics. An upper neg…