Table 3.

Contribution of the MexCD-OprJ efflux operon to antimicrobial susceptibility of P. aeruginosa biofilms

AntibioticK767 (wild type)K1521 (K767 ΔmexCD-oprJ)K1536 (K767nfxB; hyperexpresses mexCD-oprJ)
MBEC (μg/ml)MIC (μg/ml)MBEC (μg/ml)MIC (μg/ml)MBEC (μg/ml)MIC (μg/ml)
Aztreonam1,024321,024161,02464
Chloramphenicol1,0241281,0241281,024256
Ciprofloxacin16<2162162
Erythromycin1,024321,024641,024256
Gentamicin164644644
Piperacillin1,024321,024321,02432
Tetracycline51264512128512128
Tobramycin64<2322322