Pulse Radiolysis of Catalase in Solution. I. Reactions of O⁻₂with Catalase and Its Compound I

Abstract

The time-course of absorption changes of oxygen-saturated solutions of bovine-liver catalase after pulse radiolysis have been studied. The rate constant of formation of Compound I due to the reaction of catalase with hydrogen peroxide has been estimated to be 2.0 x 10(7) dm3mol-1s-1. Radiation generated superoxide radicals reduce Compound I to Compound II with a rate constant of 5.0 x 10(6) dm3mol-1s-1. The formation of Compound III in the direct reaction of O2- with catalase has also been observed.