TABLE 1.

MICs of a selection of 10 triclosan-resistant isolates for triclosan and selected antibioticsa

StrainTCS level (mg/liter) at originMIC (mg/liter)
TCSCmAmpCarTeNalKmSmGm
S1HNA0.05044002000.400320140.8
M260.0750.07524000.100160
M170.0750.100>8501000.20020.4
M30.0750.10080.8000.4
M130.0750.1008>4008000.800
M270.1000.1008>400800
M210.1000.250>82001000.200>32020.4
M280.1000.250200400>1
M340.1000.5008800
M330.1001.00022001001600.4
M360.2008.000
M36+NA>16.000NDNDNDNDNDNDNDND
  • a Abbreviations: Te, tetracycline; Amp, ampicillin; Car, carbenicillin; Nal, nalidixic acid; Cm, chloramphenicol; Km, kanamycin; Sm, streptomycin; Gm, gentamicin; NA, not applicable; ND, not determined. The isolates are sorted based on the MICs for TCS and their antibiotic cross-resistance profile, and for every mutant, the level of triclosan observed at the origin of the isolate is given. Mutant M36+ is a derivative of mutant M36. Increased MICs are indicated in bold. A minus sign indicates that the MIC of the isolate is identical to that of the parent strain.