Checkerboard assays of fluconazole-resistant C. albicans clinical isolates overexpressing the multidrug efflux pumps CDR1, CDR2, and MDR1 and/or overexpressing the drug target ERG11 as indicateda

Strain and compoundCompound concn (μg/ml)FLC concn (μg/ml)FICIOutcome
95-142 (CDR1/CDR2)
96-25 (MDR1/ERG11)
12-99 (all four genes)
  • a MIC values were determined by a broth microdilution assay according to CLSI protocol M27-A3 (2008) using 50% growth reduction as the cutoff for the reported MIC values. MIC1, the MIC of the compound or FLC alone; MIC2, the MIC of the compound or FLC in the presence of FLC or compound, respectively. FIC, fractional inhibitory concentration; FICI, fractional inhibitory concentration index. *, values were converted from μM to μg/ml.