TABLE 1.
Treatment | ATP efflux (pmol)a
|
Loss of cell viability (%)b
|
||
---|---|---|---|---|
Without Hst 5 | With Hst 5 | Without Hst 5 | With Hst 5 | |
Buffer | 14 ± 6 | 1,168 ± 513 | 0 | 98 ± 3 |
DIDS | 46 ± 3 | 88 ± 20c | 0 | 8 ± 7c |
NPPB | 43 ± 15 | 227 ± 43c | 0 | 50 ± 6c |
Niflumic acid | 20 ± 17 | 214 ± 76c | 0 | 49 ± 5c |
C. albicans cells were preincubated with DIDS (1 mM), NPPB (1 mM), niflumic acid (1 mM), or buffer alone for 2 h at 37°C, and then Hst 5 (31 μM) was added to cells for 30 min. The ATP released from 106 cells was quantified by using a luciferin-luciferase assay. The values are means ± standard deviations for at least three independent experiments.
C. albicans cells were preincubated with DIDS, NPPB, or niflumic acid (all at a concentration of 1 mM) for 10 min at 37°C and then treated with 31 μM Hst 5 for 1.5 h. Control cells were maintained in sodium phosphate buffer alone. Cells were plated after treatment to assess the loss of viability, determined as follows: [1 − (CFU of treated cells/CFU of control cells)] × 100. The values are means ± standard deviations for at least three independent experiments.
The difference between cells treated with Hst 5 alone and cells pretreated with inhibitor was significant at a P value of ≤0.01, as determined by a Student t test.