Figure 4. Kinetic analysis of papain and Cal1 enzyme inhibition by selected inhibitors.

Plots of secondary and primary kinetic data for inhibition of papain (A) and Cal1 (B) used to derive detailed kinetic parameters reported in Table 2: E-64 (diamonds – solid green); 22a (closed circles – dashed red); 31 (squares – solid orange); 36 (open circles – dashed blue). The observed rate constants (k_obs) shown in the double reciprocal plots were measured from non-linear fitting of “progress curves” for product formation from substrate. Exemplar progress curves are shown for Cal1 inhibition by E-64.