Fig. 7.

Progress curve of fluorogenic substrate (Boc-EAR-MCA) hydrolysis by trypsin in the presence of PN2KPI and the secondary plot. (A) Hydrolysis of Boc-EAR-MCA (6 µM) by trypsin (0.5 nM) in the presence of varying concentrations of PN2KPI (0–20 nM) were monitored for 2,500 s. Inhibitor concentrations used are shown on the right, adjacent to the respective curve. (B) Secondary plot of k_obs values versus PN2KPI concentration. The k_obs (s⁻¹) values for each inhibitor concentration were calculated from the averaged values (± SD) of five assays each done in duplicate.