Figure 3. Pkc1 enables basal tolerance to ergosterol biosynthesis inhibitors in part via the MAPK cascade in Candida albicans.

(A) Deletion of PKC1, BCK1 or MKC1 reduces tolerance to fluconazole (FL), fenpropimorph (FN), and terbinafine (TB) in MIC assays. Assays were performed in YPD medium at 35°C with strains derived from the WT SN95. Data was analyzed after 72 hours growth as in Figure 1A. The minimum drug concentration that inhibits growth by 80% relative to the drug-free growth control (MIC₈₀) is indicated for each strain. (B) Deletion of PKC1, but not MAPK components, creates a fungicidal combination with the ergosterol biosynthesis inhibitors in C. albicans. MIC assays with four-fold dilutions of FL, FN, and TB were performed in YPD and incubated for 48 hours at 35°C. Cells from the MIC assays were spotted onto YPD medium and incubated at 30°C for 48 hours before plates were photographed.