FIG 2.

CaRib1 is essential for full virulence in relevant model systems. (a) The Carib1Δ/Δ deletion strain as well as the wild-type 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. Deletion of CaRIB1 causes the complete absence of cytotoxicity toward mammalian HeLa cells (determined by LDH activity and shown as average and SEM). (b) The Carib1Δ/Δ deletion, 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 deletion strain and the wild type. (c) Mice were infected with the same strains through tail vein injection. The C. albicans strain without CaRib1 is completely avirulent in a mouse model of systemic infection. Statistical analyses for panels a and b were performed by one-way ANOVA, with Bonferroni correction. ****, P < 0.0001. Statistical analysis for panel c was performed by a log rank Mantel-Cox test. *, P < 0.05; **, P < 0.01.