FIG. 3.

Behavior of the conditional C. albicans FBA1 mutants in liquid media. (A) Growth of the conditional C. albicans FBA1 mutants continues for hours after the addition of methionine and cysteine. C. albicans strains were grown at 30°C in SC medium containing (black squares) or lacking (white squares) methionine and cysteine. Results for FBA1/FBA1 (RIM1000), MET3-FBA1/FBA1 (ARC102), and MET3-FBA1/fba1 (ARC103) are shown. In replicate experiments, strain ARC101 (FBA1/fba1) grew similarly to RIM1000 and ARC102, whereas ARC104 and ARC105 grew similarly to ARC103 (not shown). (B) MET3-FBA1 shutoff is static, not cidal. C. albicans ARC103 cells (MET3-FBA1/fba1) from the culture containing methionine and cysteine were subcultured into fresh SC medium containing (black squares) or lacking (white squares) methionine and cysteine, and their growth was monitored. Similar data were obtained in replicate experiments. OD₆₀₀, optical density at 600 nm.