The KCN-Insensitive Respiration of Animal's Mitochondtria

摘要

With the reconstituted respiratoiy enzymes it has been demonstrated that the electrons transferred in the respiratory chain can be leak out of the chain from the cytochromes to reduce H_2O_2. About 2% of oxygen is consumed in the generation of H_2O_2 in mitochondria has been proved by B.Chance et al. The precursor of H_2O_2 is the superoxide anion O_2 which is formed through a single electron reduction of O_2 by the leaked electrons from the substrate side of the chain. If link the generation of H_2O_2 by the substrate side of respiratory chain and the reduction of H_2O_2 by the electrons leaked from the cytochromes, a metabolic pathway of O_2 →H_2O_2 →H_2O is formed.