Pseudomonas cytochrome c peroxidase. Initial delay of the peroxidatic reaction. Electron transfer properties.

A delay of some seconds is observed in the reaction of Pseudomonas cytochrome c peroxidase if the reaction is initiated by adding the enzyme to the reaction mixture containing reduced electron donor and hydrogen peroxide. This lag phase is avoided if the enzyme is incubated with the reduced electron donor and the reaction is started by adding hydrogen peroxide. The nature of the initial delay has been studied and it is shown that the peroxidase is reduced before a steady-state rate in the peroxidatic reaction is reached. The ability of the peroxidase to accept electrons from various electron donors emphasizes its cytochrome-like properties.