FIG 6 .

In vitro virulence assessment of farnesylation and postprenylation processing enzymes. (A) The ram1Δ, rce1Δ, and ste14Δ mutant strains display decreased survival in macrophages. Wild-type H99 and ram1Δ (SKE1), rce1Δ (SKE51), and ste14Δ (YSB1187) mutant strains were each coincubated with activated J774.1 cells for 1 h, followed by removal of nonphagocytosed yeast cells. Cryptococcal cell survival was assessed at 24 h by quantitative culture. Data represent mean results ± standard errors from 4 replicates for each WT-mutant pair. P < 0.05 for all strains versus WT, as determined by one-way ANOVA. (B) The ram1Δ, rce1Δ, and ste14Δ mutant strains have growth defects in DMEM macrophage medium. Wild-type H99 and ram1Δ (SKE1), rce1Δ (SKE51), and ste14Δ (YSB1187) mutant strains were incubated overnight in YPD, normalized and diluted into DMEM, and plated in a 96-well plate. Cells were grown for 48 h in a microplate reader, with absorbance readings taken every hour.