Table 3.

Drug resistance of E. coli KAM3 harboring plasmids carrying putative drug transporter ORFs under control of thetrc promotera

CompoundMIC (μg/ml) without plasmidMIC (μg/ml) with plasmid carrying ORF for transporter of type:
MFRNDSMR (pTrcHydgFE)
pTrcHyceEpTrcHyceLpTrcHbcrbpTrcHyidYpTrcHyjiOpTrcHcusABpTrcHyegOpTrcHacrDpTrcHacrEF
Chloramphenicol0.390.390.390.39 0.78 0.78 0.390.390.39 6.25 0.39
Tetracycline0.390.390.39 3.13 0.390.390.390.39 0.78 3.13 0.39
Minocycline0.200.200.200.200.200.200.200.200.20 3.13 0.20
Erythromycin3.133.133.133.133.133.133.133.133.13 200 3.13
Nalidixic acid0.780.780.780.780.780.780.78 1.56 1.56 3.13 1.56
Norfloxacin0.0250.025 0.05 0.0250.025 0.05 0.025 0.05 0.05 0.10 0.025
Enoxacin0.050.05 0.10 0.050.050.050.050.050.05 0.39 0.05
Kanamycin6.256.256.25 25 6.256.256.256.25 12.5 6.256.25
Vancomycin200200200200200200200200200200200
Fosfomycin1.56 6.25 1.56 6.25 1.561.56 3.13 3.13 3.13 1.56 3.13
Doxorubicin3.133.133.133.133.133.133.133.133.13 >200 3.13
Novobiocin1.561.561.561.561.561.561.561.56 6.25 50 1.56
Rifampin6.256.256.256.256.256.256.256.256.256.256.25
Trimethoprim3.133.133.133.133.133.133.133.133.13 100 3.13
Acriflavine12.512.512.5 25 12.5 50 12.512.512.5 400 12.5
Crystal violet0.780.780.780.780.780.780.780.780.78 12.5 0.78
Ethidium bromide12.512.512.512.512.5 25 12.512.512.5 400 12.5
Rhodamine 6G6.256.256.256.256.256.256.256.256.25 400 6.25
Methylviologen100100100100100100100100100 200 100
TPP6.256.256.256.256.25 12.5 6.256.256.25 200 6.25
CCCP6.256.256.256.256.256.256.256.256.256.256.25
Benzalkonium3.133.133.133.133.133.133.133.133.13 50 3.13
SDS50505050505050 100 >400 >400 100
Deoxycholate1,2502,5001,2501,2501,2501,2501,250 5,000 >40,000 >40,000 5,000
  • a Values in bold differ significantly from the KAM3 control strain value, and 0.1 mM IPTG was added to agar plates. pTrcHyajR, pTrcHydeA, pTrcHydeF, pTrcHynfM, pTrcHydhC, pTrcHydiM, pTrcHyebQ, pTrcHyegB, pTrcHyieO, pTrcHyegN, pTrcHsugE, pTrcHmdlA, pTrcHmdlB, pTrcHybjZ, pTrcHyddA, pTrcHyojI, pTrcHyojH, and pTrcHyhiH did not alter MIC values.

  • b pTrcHbcr conferred bicyclomycin resistance (MIC, 25 μg/ml for KAM3 versus 400 μg/ml for KAM3/pTrcHbcr).