FIG 6.

CaSef1 is essential for full virulence in a systemic mouse model of infection. (a) The Casef1Δ/Δ deletion strain as well as the wild-type, the phosphorylation mutant, and the reintegrant strains were added to mammalian HeLa cells. After 24 h of incubation at 37°C and 5% CO₂, cytotoxicity was determined based on LDH release in the culture supernatant. Data are shown as average and SEM. Neither deletion nor mutation of CaSEF1 causes a decrease of cytotoxicity toward mammalian HeLa cells (determined by LDH activity). (b) The Casef1Δ/Δ deletion, phosphorylation mutant, wild-type, and reintegrant strains were added to mammalian HeLa cells. After 90 min of incubation at 37°C and 5% CO₂, adhesion was determined based on number of CFU. Average values and SEM are shown. There is no significant difference between the mutant strains and the wild type. (c) Mice were infected with the same strains through tail vein injection. The C. albicans strain without CaSef1 is less virulent in a mouse model of systemic infection. Statistical analyses of panels a and b were performed by one-way ANOVA, with Bonferroni correction. **, P < 0.01. Statistical analysis of panel c was performed by a log-rank Mantel-Cox test. **, P < 0.01.