FIG 7.

Ptp1 plays minor roles in growth, stress response, and virulence factor production. (A and B) Northern blot analyses using the total RNA isolated from WT (H99) strain and ptp2 and ptp2 hog1 mutants, which were grown to the mid-logarithmic phase at 30°C in YPD medium and were then exposed to 2.5 mM H₂O₂ or 1 M NaCl. Each membrane was hybridized with a PTP1-specific probe, washed, and developed. Ethidium bromide staining results of rRNA were used as loading controls. (C) Each indicated strain grown to the mid-logarithmic phase was 10-fold serially diluted and spotted onto YPD medium containing CdSO₄ (25 μM), H₂O₂ (3 mM), or flucytosine (600 μg/ml). Cells were incubated at 30°C for 2 to 4 days and photographed. To determine thermotolerance, cells were spotted onto YPD agar medium and incubated at 30°C, 37°C, or 39 to 40°C for 4 days and photographed. (D) Cells were spotted onto niger seed medium containing 0.1% or 0.5% glucose, incubated at 30°C, and photographed daily. (E) Roles of Ptp1 and Ptp2 in urease production. Cells were spotted onto the Christensen's medium, incubated at 30°C, and photographed daily.