Zur Kenntnis des Kathepsins und Papains.

Abstract

The authors sought to determine whether, or to what extent, the proteolytic action of "fully active" cathepsin could be ascribed to the minute quantities of SH compounds present in elutions of organ-dry powder freed from zookinase. The elimination of SH-, oxidized by iodoacetic acid, is not considered to be proof of an activation by SH-compounds, since the proteolytic action of cathepsin and papain is known to be completely inhibited by minute quantities of iodoacetic acid. Cyano-acetic acid, which is also said to accelerate the auto-oxidation of SH-compounds, did not influence the velocity of dissociation. Iodine stopped the proteolytic action of cathepsin and papain. S.S-compounds were present in suspensions of both enzymes, and could easily be changed into SH-compounds. Dissociation expts. showed that the amt. of gelatine hydrolyzed by cathepsin was less under aerobic than under anaerobic conditions.