TABLE 6.
Yeast strain sensitivity to PY compounds
| Compoundb | Yeast inhibition (cm in spoke assay)a
|
|||||||
|---|---|---|---|---|---|---|---|---|
| Cp-yeast type I | Cp-yeast type II | Hu-yeast | Pf-yeastS | Pf-yeastR | Tg-yeast | Pc-yeast | Sc-yeast | |
| Trimetrexate | 2.6 | 2.7 | 3 | >3.5 | 3 | 2.5 | 2.1 | − |
| PY 359 | − | − | − | 3.6 | 0.8 | − | − | − |
| PY 361 | 2.5 | 2.9 | 3.4 | >3.5 | 2.8 | 1.9 | 1.9 | − |
| PY 365 | 2.4 | 2.7 | 2.8 | 3.4 | 1.3 | 1.9 | 1 | − |
| PY 460 | − | − | − | >3.5 | 1.4 | − | − | − |
| PY 461 | 1.4 | 1.7 | 2.8 | >3.5 | 2.9 | 1.7 | 1.5 | − |
| PY 468 | − | − | 0.9 | 3.4 | 2 | − | − | − |
| PY 488 | 1.5 | 1.7 | 2.6 | >3.5 | 2.8 | 1.7 | 1.8 | − |
| PY 489 | 1.8 | 1.8 | 2.5 | >3.5 | 3 | 1.7 | 1.9 | 0.9 |
| PY 490 | 2.7 | 2.9 | 3.1 | >3.5 | 2.7 | 2.2 | 1.2 | − |
| PY 497 | 1.8 | 2.8 | 3.1 | >3.5 | 3.1 | 2.1 | 1.3 | 0.7 |
| PY 821 | − | − | − | − | − | − | − | − |
| PY 823 | 0.8 | 0.8 | 0.8 | 1.7 | 1.4 | 0.8 | − | − |
| PY 826 | 0.8 | 0.8 | 0.8 | 0.8 | 0.8 | − | − | − |
| PY 833 | − | − | − | − | − | − | − | − |
| PY 841 | − | − | − | 2.1 | 1.9 | − | − | − |
| PY 842 | − | − | − | 2.2 | − | − | − | − |
| PY 875 | 1.1 | 1.7 | 2 | >3.5 | 2.9 | 1.9 | 1.6 | − |
| PY 888 | − | − | − | >3.5 | 2.5 | − | 1 | − |
| PY 890 | − | − | − | >3.5 | − | − | − | − |
| PY 896 | 2.7 | 3.2 | 3.5 | >3.5 | >3.5 | 3.6 | 3.5 | 2.4 |
| PY 898 | 2.3 | 2.7 | 3.1 | >3.5 | >3.5 | 3 | 2.5 | − |
| PY 899 | 2.7 | 2.8 | 3.1 | >3.5 | 3.2 | 2.7 | 2.6 | − |
a
Numbers represent distance from the center of the plate to the beginning of yeast growth (kill zone) and are the averages of three independent experiments. The standard deviations were ≤0.5 cm. −, no inhibition detected. Pf-yeastS, pyrimethamine-sensitive Pf-yeast; Pf-yeastR, pyrimethamine-resistant Pf-yeast.
b
Boldface indicates compounds that were particularly effective against C. parvum DHFR-TS.