[13C]Valine metabolism in methylmalonicacidemia using nuclear magnetic resonance: propinonate as an obligate intermediate.
[Alpha-13C]- and [alpha,beta-13C]valine were administered sequentially to a patient with methylmalonicacidemia to clarify the metabolic pathway of valine from methylmalonic acid semialdehyde to methylmalonyl-CoA. Methylmalonic acid was isolated from multiple urine samples, purified, and analyzed by 13C nuclear magnetic resonance spectroscopy. Contrary to the widely accepted view, the results show unequivocally that methylmalonic acid semialdehyde is decarboxylated to propionate before conversion to methylmalonyl CoA.
D000592:Amino Acid Metabolism, Inborn Errors / Q000378:metabolism*; D002648:Child; D003065:Coenzyme A / Q000378:metabolism; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D008314:Malonates / Q000378:metabolism*; D008764:Methylmalonic Acid / Q000378:metabolism* / Q000652:urine; D011422:Propionates / Q000378:metabolism*; D014633:Valine / Q000378:metabolism*
D008314:Malonates; D011422:Propionates; D008764:Methylmalonic Acid; D014633:Valine; D003065:Coenzyme A