Contribution of Vitamin B12 to the Activation of Apoenzyme for the Formation of Pyruvate Oxidase System in Rats

Abstract

The authors (1) have reported a study on the contribution of vitamin B12 (B12) to the formation of carboxylase in B12-deficient rats. The increase in car boxylase activity was always observed in the group receiving vitamin B12, whereas it was negative in the B12-deficient group. These experiments were repeated and the addition of vitamin B12 to the diet was confirmed to increase the formation of carboxylase (2).

Decrease of Apoenzyme Activities in Vitamin-Deficient Animals

“…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).…”

“…In the present study (4), further experiments have been attempted con cerning the effects of vitamin B12-deficiency on the activation of various apoenzymes using the experimental procedure quite similar to that already described.…”

“…The only result was that the change of pyruvate-apooxidase activity was recognized in B1-deficient rats. The second attempts (5)…”