[Spectral properties of the prosthetic group of Penicillium vitale catalase].

Differences in the absorption spectrum of the Penicillum vitale catalase in the visible region as compared to the absorption spectrum for catalase of animal origin are established to be due to the prosthetic group of the enzyme. A molecule of P. vitale catalase is determined to contain 0.051 +/- 0.0003% of iron. It corresponds to two iron atoms per enzyme molecule and to a twice as low content of iron as in a molecule of the bovine liver catalase. An assumption is advanced that the P. vitale catalase contains two hemin groups located in two protein subunits.