Fig 1.

C. albicans ssu1Δ mutants are growth sensitive to sulfite and cysteine. (A) Overnight cultures of strains SC5314 (wild type), SSU1M4A/B (ssu1Δ) and SSU1KS2A/B (ssu1Δ + SSU1) were serially 10-fold diluted, and aliquots were inoculated on YPD-TA agar plates containing 200 μM sodium sulfite. As a control, YPD-TA agar plates without sodium sulfite were used. The agar plates were incubated for 28 h at 30°C. (B and C) C. albicans overnight cultures of the same strains were diluted 1:100 in fresh SD medium containing increasing concentrations of cysteine (B) or methionine (C). The optical densities of the cultures were measured after growth for 8 h and 24 h at 30°C. The addition of cysteine to the medium significantly reduced the growth of the ssu1Δ mutant compared to wild-type and reconstituted strains. The two independently constructed mutants and complemented strains behaved identically, and the results for only one of them are shown.