The denaturation of trypsin

The denaturation of α- and β-trypsin in alkaline and neutral solution was studied. The denaturation of α-trypsin was a strict second-order reaction at neutrality. However, the denaturation of β-trypsin was not a pure secondorder reaction at the same pH. Calcium ion retarded the rate of β-trypsin denaturation to a greater extent than that of α-trypsin. In alkaline solution, trypsin has very short half life (t _{case1 2} < 30 minutes). On the other hand, the denaturation of immobilized trypsin in alkaline solution is a first-order reaction as is immobilized chymotrypsin. The rates of these two denaturations are similar. Calcium ion does not affect the rate of trypsin denaturation in alkaline solution.