The Succinoxidase System in Oyster Muscle

The importance of the role which the C₄-dicarboxylic acids play in tissue respiration was pointed out by Szent-Györgyi in 1937. It is now known that succinic dehydrogenase is one of the few dehydrogenases which react directly with the cytochromes, and the ‘succinoxidase’ system has been investigated in a large number of vertebrate tissues. The action of succinate on the oxygen uptake of a few invertebrate tissues has been studied, but no detailed consideration has been given to the possible occurrence of a succinoxidase system. This system becomes especially important in view of the varied response of such tissues to agents like cyanide and azide, which have a marked effect on cytochrome oxidase.