FIG 2.

Deleting EFG1 in the cas5 mutant enhances susceptibility to caspofungin. (A) Cell morphologies of the efg1 mutant, cas5 mutant, and cas5 efg1 double mutant compared to the wild type (SN250). Cells were grown in YPD at 30°C. (B) Cells of the wild type (SN250), efg1 mutant, cas5 mutant, and cas5 efg1 double mutant were serially diluted 10-fold and spotted onto YPD solid plates containing caspofungin (0, 20, 40, and 80 ng/ml). Photos were taken after 2 days of growth at 30°C. (C) Quantification of caspofungin susceptibility. A total of ∼10³ cells of the indicated strains was incubated in YPD liquid medium with or without 20 ng/ml of caspofungin. Aliquots were then plated onto YPD plates. The viability was calculated as a ratio of colonies formed in plates of caspofungin-treated cells versus untreated cells. Data represent means and SEM from three independent experiments. Significance was measured with unpaired t test in GraphPad Prism. ****, P < 0.0001. (D) An assay for susceptibility of the indicated strains to caspofungin was performed and analyzed as described for Fig. 1B.