TABLE 5.

Determination of the MICs and survival rates

Type of compoundCompoundsMIC,a,b survival ratec for:
Wild typeΔliaF mutantΔliaIH mutant
Cell wall antibioticsBacitracin300300300
Cefotaxime0.1, 1000.1, 1000.05, 10−2
Cephalexin0.25, 1000.25, 1020.125, 101
Daptomycin1.25, 1001.25, 1000.6, 10−1 to 10−2
Enduracidin25, 10012.5, 10012.5, 10−3
Nisin102.510
Fosfomycin100, 100200, 10050, 10−3
Vancomycin0.50.50.5
Oxidative stress reagentsCumene hydroperoxide0.006, 1000.006, 1000.006, 10−2
Hydrogen peroxide1.50.51.0
Menadione5, 1001.25, 1002.5, 10−1
Plumbagin5, 1002.5, 1001.25, 10−1
Sodium selenite500, 100500, 100125, 10−2
t-Butyl hydroperoxide1, 1001, 1000.5, 10−1
OthersCetylpyridinium chloride0.50.50.5
Domiphen bromide0.1250.030.125
Phenylarsine oxide0.10.10.05
  • a MICs are in μg/ml with the exception of cumene hydroperoxide (%), t-butylhydroperoxide (mM) and hydrogen peroxide (%).

  • b Values indicating explicit sensitivity or resistance of the ΔliaF and ΔliaIH mutant strains versus that of the wild-type are highlighted in bold.

  • c Survival rates were determined by serial dilution spot tests on Mueller-Hinton agar plates at the following “critical” compound concentrations: fosfomycin, 250 μg ml−1; cefotaxime, 0.1 μg ml−1; enduracidin, 0.01 μg ml−1; daptomycin, 0.15 μg ml−1; cephalexin, 0.2 μg ml−1; plumbagin, 2.5 μg ml−1; menadione, 1.25 μg ml−1; t-butyl hydroperoxide, 0.3 mM; cumene hydroperoxide, 0.003%; sodium selenite, 125 μg ml−1. All values are given relative to the result for the wild type as a reference, which was therefore set to 100. See Fig. S3 in the supplemental material for the original data and experimental details.