Chemical Nature of Catalase

Abstract

The chemical nature of catalase has been studied by a number of authors. The experiments of Zeile 1 and of Stern 2 indicate that the catalase molecule is probably a chromoprotein in which the hemin group is related to that of the natural blood pigments. Recently Agner 3 reported that if horse liver catalase is dialyzed against N/10 or N/100 HCl the enzyme splits into 2 inactive components, one of a low molecular weight which dialyses through the cellophane membrane and which is possibly hemin and another component which remains within the bag and which is a protein. If the 2 neutralized components are mixed, an active preparation is again obtained, according to Agner.

Having the intention of making certain studies on the basis of Agner's report, we first attempted to repeat his experiment. The technique is simple but we were not able to confirm his results. The only difference between his and our technique is in the species of animal from which the liver was derived. Horse liver, which Agner used, is practically unobtainable in our locality. We have, however, tried beef, rabbit, and rat liver, respectively. We followed the experiments of Agner in every detail, dialyzing the purified catalase against N/10 or N/100 HCl, for 10 to 48 hours. No splitting (inactivation) of the catalase could be obtained. With stronger HCl irreversible inactivation of the catalase took place, due to a marked decrease in pH inside the dialyzing bag.