The action of trypsin on insulin

Abstract

Purified trypsin has less action than the trypsin originally used. Using 4 times recrystallized insulin and purified trypsin, the non-protein N formed is not much greater than that produced in the buffer alone, but in the presence of trypsin alone the physiol. potency is diminished to a somewhat greater extent than in its absence. Ultracentrifugal examination of the recovered insulin shows it to have become less homogeneous than the original. The action of trypsin on insulin is thus slight but the possibility of the hydrolysis of 1 or 2 peptide bonds, with a diminution of potency of 10-20% is not excluded.