Proteolytic susceptibility of alpha-amylase of the pancreas of swine deprived of its structural calcium

Abstract

Hog pancreas alpha-amylase (alpha-1-4-glucan-glucan hydrolase, E.C.3.2.1.1) lost its structural calcium by action of EDTA at 20 degrees C.Enzymatic activity experimented a decrease whereas a big increase in proteolytic susceptibility to bovine pancreas trypsin (E.C.3.4.4.4) was shown.Native alpha-amylase had an activity of 2,730 mg maltose/min X mg enzyme and a Km of 0.222% amylose, the activity of calcium depleted amylase being of 1,640 mg maltose/min X mg enzyme and Km 0.571% amylose.Simple methods for evaluating proteolytic susceptibility of alpha-amylase micro-amounts against trypsin action, and for the measurement of alpha-amylase activity in polyacrylamide rod gels were also described.