TABLE 1.
Checkerboard assay of S. cerevisiae strains overexpressing multidrug efflux pumps CaCDR1 and CaMDR1a
| Strain and compound | Compound concn (μg/ml) |
FLC concn (μg/ml) |
FICI | Outcome | ||||
|---|---|---|---|---|---|---|---|---|
| MIC1* | MIC2* | FIC | MIC1 | MIC2 | FIC | |||
| AD/CaCDR1 | ||||||||
| 1 | 69 | 0.54 | 0.008 | 300 | 75 | 0.25 | 0.26 | Synergy |
| 2 | 70 | 0.14 | 0.002 | 300 | 75 | 0.25 | 0.25 | Synergy |
| 3 | 73 | 0.07 | 0.001 | 300 | 75 | 0.25 | 0.25 | Synergy |
| 4 | 75 | 0.59 | 0.008 | 300 | 75 | 0.25 | 0.26 | Synergy |
| AD/CaMDR1 | ||||||||
| 1 | 69 | 0.13 | 0.002 | 15 | 3.8 | 0.25 | 0.25 | Synergy |
| 2 | 70 | 0.27 | 0.004 | 15 | 3.8 | 0.25 | 0.25 | Synergy |
| 3 | 73 | 1.13 | 0.016 | 15 | 3.8 | 0.25 | 0.27 | Synergy |
| 4 | 75 | 0.14 | 0.002 | 15 | 3.8 | 0.25 | 0.25 | Synergy |
| 5 | 80 | 0.63 | 0.008 | 15 | 3.8 | 0.25 | 0.26 | Synergy |
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, MIC of compound or FLC alone; MIC2, MIC of 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.