Figure 4
Autoactivation of ferret trypsinogens and human cationic trypsinogen (PRSS1). Trypsinogens (2 µM) were incubated at 37 °C, in 0.1 M Tris-HCl (pH 8.0), and 0.05% Tween 20 (final concentrations). Aliquots of 2 µL were withdrawn at the indicated times and trypsin activity was measured with the N-CBZ-Gly-Pro-Arg-p-nitroanilide substrate. (A) Autoactivation in the presence of 10 mM CaCl2, with no initial trypsin added. The arrow indicates addition of 28 ng/mL human enteropeptidase (EP). Mean values with S.D. are shown. (B) Autoactivation in the presence of 1 mM CaCl2, with 10 nM initial trypsin added. Mean values from two experiments are shown.
