FIG. 6.

Strains with TOK1 disruption and killing-tolerance to Hst 5 have reduced ATP efflux. C. albicans strains were grown to late log phase in YNB, and then 10⁶ cells from each strain were mixed with Hst 5 (31 μM) and incubated for the indicated times to establish ATP efflux. Closed squares, CAI4 (TOK1/TOK1); open triangles, DBT2 (TOK1/tok1); closed circles, DBT3(tok1/tok1). Extracellular ATP was measured by luminometry of cell supernatants and is expressed as nanomoles of ATP per 10⁶ cells. Each data point represents the mean ± standard deviation of at least three independent experiments. The fitted regression lines have slopes of 6.3, 11.2, and 24.9 nmol of ATP/h · 10⁶ cells, respectively, for zero, one, and two active TOK1 genes present.