FIG 6.

Urease activity for cells of the parent strain and amoeba-selected strains. The urease activity of cryptococcal cells were detected by using the rapid urea broth (RUH) method. Amoeba-passaged isolates are labeled with numbers preceded by the letters H, A, and F to indicate their origin from strains H99, A1-35-8, and Ftc555-1, respectively. HP, AP, FP: parental strains; HC, AC, FC: controls. The assay was performed in triplicate for each time point. Error bars represent SD. *, P < 0.1; **, P < 0.01; ***, P < 0.001; unpaired t test. OD₅₇₀, optical density at 570 nm.