Determination of MIC for wild type (NTUH-K2044), mutant (NTUH-K2044ΔcpxAR) and complemented (NTUH-K2044ΔcpxARΩcpxAR) strains.

E-strips were used to determine the precise MIC for different group of antibiotics such as amikacin, ampicillin, cefepime, cefotaxime, ceftazidime, ceftriaxone, chloramphenicol, ciprofloxacin, erythromycin, kanamycin, nalidixic acid, ofloxacin, polymyxin, rifampicin, tetracycline, tobramycin, trimethoprim, and vancomycin following the CLSI guidelines.aFold change is the ratio of MICs for NTUH-K2044 and NTUH-K2044Δ cpxA.