CYTOCHROME C AND THE ROLE OF ZINC IONS IN ELECTRON TRANSPORT IN RAT LIVER MITOCHONDRIA

The inhibition of electron transfer by zinc ions in the electron transport system of the rat liver mitochondria was investigated. There was an increase in the rate at which oxygen was consumed in rat liver mitochondria pre-incubated with cytochrome c. However, the rate of inhibition of oxygen consumption by zinc ions was significantly reduced [P<0.01] in the liver mitochondria that was pre-incubated with cytochrome c. Zinc ions inhibited the electron transfer at the complex II, which is at the level of succinate electron transfer and not at the level of NADH [Complex I] of the rat liver mitochondria.