Table 5.

Contribution of the MexXY efflux operon to antimicrobial susceptibility of P. aeruginosa biofilms

AntibioticK767 (wild type)K1525 (K767 ΔmexXY)
MBEC (μg/ml)MIC (μg/ml)MBEC (μg/ml)MIC (μg/ml)
Aztreonam1,0243251216
Chloramphenicol1,024128>1,024128
Ciprofloxacin16<28<2
Erythromycin1,02432>1,02432
Gentamicin16416<2
Piperacillin1,02432>1,02432
Tetracycline5126451232
Tobramycin64<232<2