“…The authors reported a study on the contribution of vitamin B12 to the for mation of carboxylase in B12-deficient rats. Further researches were made to elucidate whether vitamin B12 activates the pyruvate oxidase system in B12-deficient rats (2). Experiments were first carried out in connection with the investigation by Gunsalus, and further confirmation was made from the enzymatic aspects for the activation of endogenous respiration level under several additive conditions, involving flavin-adenine dinucleotide, and fuma rate (3).…”