Figure 3. The inhibition effect of PMSF (at PMSF concentrations to achieve 40% reduction in activity with respect to the substrates below) on the activities of CE and PCE (pH 7.0 at 25°C). The activities were measured with para-nitrophenylacetate and butyrylthiocholine as substrates for CE and PCE, respectively. PMSF concentration for CE was 1 mM and for PCE was 0.5 mM. All data are reported as mean ± standard error. N = 3. Standard deviations for CE-incubated groups range from 5.2 to 7.9%, and for PCE groups from 3.8 to 5.3%.