Fig. 3.
Selected inhibitors efficiently inhibit the catalytic activity of WNV NS2B-NS3pro. Before the addition of the pyroglutamic acid Pyr-Arg-Thr-Lys-Arg-7-amino-4-methylcoumarin substrate (25 μM), the purified WNV proteinase (10 nM) was co-incubated for 30 min with increasing concentrations of the inhibitors. The residual activity was then monitored continuously at λex = 360 nm and λem = 465 nm to determine the initial velocity of the reactions. The initial velocity was calculated as a percentage of residual activity versus the untreated proteinase (control). Refer to Table 1 for the ligand structures.