Figure 2.

Trypsin inhibitor activity of cpBPTI variants. The native BPTI variants at the indicated total concentrations were incubated with bovine trypsin, at a concentration of 3.4 μM, for either 20 or 120 min, as indicated. The residual trypsin activity was determined spectrophotometrically using a chromogenic substrate, benzoyl-l-arginine 4-nitroanilide, and monitoring the absorbance at 405 nm.