Vitamin B 12 and choline synthesis from glycine in vivo

Abstract

The effect of vitamin Bi 12 on choline synthesis from glycine was studied in 2–3-day-old baby pigs fed an α-protein synthetic milk ration containing 2.2% glycine, 0.8% methionine, and less than 0.01% choline. In the groups receiving vitamin B 12, histological examination of the livers revealed no fatty infiltration characteristic of a choline deficiency; whereas, in the B 12-deficient groups all the animals had markedly fatty livers. These results indicate that vitamin B 12 is required for the synthesis of methyl groups from glycine and that glycine will serve as a methyl source only in the presence of B 12.