Anaerobic oxidations. On ferricyanide as a reagent for the manometric investigation of dehydrogenase systems

Abstract
A preliminary account was given of the use of ferricyanide as a reagent for the manometric study of dehydrogenase systems. Succinate and choline rapidly reduced ferricyanide in the presence of their respective dehydro-genases in intact tissue slices. The action of cozymase in catalyzing the reduction of ferricyanide by dl-lactate, l-malate. dl-glycerate and l (+) glutamate in the presence of their dehydrogenases was shown to take place with intact tissue slices. Lysed blood cells (human, ox) formed good sources of lactic and malic acid dehydrogenases, cozymase being necessary for their actions. A dialysed, water clear aq. extract of rabbit skeletal muscle formed an excellent source of dehydrogenases of dl-lactic, l-malic, dl-glyceric and [alpha]-glycerophosphoric acids. The addition of cozymase was necessary to demonstrate these actions. dl-Glyceraldehyde and hexosediphosphate also rapidly reduced ferricyanide in the presence of a dialysed extract of rabbit skeletal muscle. The demonstration of these dehydrogenases in a muscle extract, by the ferricyanide technique, made it unnecessary to postulate the existence of special mutases catalyzing the reduction of pyruvic or oxaloacetic acid.