FIG. 3.

Calcium and pH dependency of HCMV PLA2 activity. HCMV (AD169, 10⁶ PFU) was incubated for 45 min at room temperature in the presence of MgCl₂ (10 mM). Where indicated, CaCl₂ (50 mM) was added prior to incubation of HCMV with BODIPY-PC and NBD-PC (A). Error bars represent standard deviations of the mean from three independent experiments. HCMV (10⁶ PFU) was incubated with BODIPY-PC for 30 min at 37°C under different pH conditions. Hydrolysis was tested by TLC (B).