Hematin iron valence in catalase and peroxidase compound I: relationship to free radical reaction mechanism.

The material in this paper is centered on the structure of compound I (first reaction intermediate) in the case of catalase and a classical peroxidase (horseradish peroxidase, HRP). The concept of a pi-cation radical is accepted for HRP but is rejected in the case of catalase. A possible mechanism for catalatic action previously proposed assumes FeV for the hematin iron of catalase and hydride ion transfer in the reduction of FeV by the second molecule of H2O2, no free radical being involved.

A study of the catalase monomer produced by lyophilization.

Lyophilization of Dounce and Mourtzikos beef liver catalase (Prep. Biochem. 11 (1981) 501-523) under specified conditions produced conformationally altered but not completely denatured catalase monomer which retained both significant catalatic activity and peroxidatic activity towards ethanol.

Identification of the FTBL protein of Sumner and Dounce as a leucine aminopeptidase.

The crystalline beef liver protein of Sumner and Dounce (A. L. Dounce, P.

Analysis of the peroxidatic mode of action of catalase.

Catalase is an enzyme which can function either in the catabolism of hydrogen peroxide or in the peroxidatic oxidation of small substrates such as ethanol, methanol, or elemental mercury (Hg0). It has been reported that native catalase can peroxidatically oxidize larger organic molecules (e.g.