Azzone 1961 J Biol Chem
|Azzone GF, Ernster L (1961) Demonstration of a requirement of high energy phosphate for the aerobic oxidation of succinate in liver mitochondria. J Biol Chem 236:1518-25.|
Abstract: Preincubation of rat liver mitochondria in a sucrose-KCl medium in the presence of 2 to 3 mM arsenate and 0.06 mM Dicumarol or 0.1 mM 2,4dinitrophenol for 3 to 4 minutes results in a marked depression of the succinoxidase capacity. No depression is found when the preincubation is made in the presence of Amytal, cysteine sulfinate, or inorganic phosphate. Addition of adenosine triphosphate after the preincubation stimulates succinate oxidation several-fold. The effect of adenosine triphosphate is not duplicated by cysteine sulfinate, inorganic phosphate, ethylenediaminetetraacetate, adenosine 5’-phosphate, cytidine triphosphate, uridine triphosphate, inosine triphosphate, or guanidine triphosphate. Similar results are obtained with mitochondria pretreated with dinitrophenol and adenosine 5’-phosphate.
The data are consistent with the conclusion that conditions leading to a depletion of the endogenous content of mitochondrial high energy phosphate result in a reversible depression of the succinoxidase capacity.
The concept is developed that the aerobic oxidation of succinate in intact liver mitochondria requires an activation by high energy phosphate. Some implications of this concept regarding the enzymic organization of mitochondrial electron transport and oxidative phosphorylation are discussed.
• Keywords: Succinate oxidation, High energy phosphate, ATP
Organism: Rat Tissue;cell: Liver Preparation: Isolated mitochondria Enzyme: Complex II;succinate dehydrogenase Regulation: ATP Coupling state: OXPHOS, ET Pathway: S