Mitochondrial compartmentation of metabolic CO2 resulting from its site of origin in relation to urea synthesis

FEBS Letters

Hems, Reginald¹ 

[1] Metabolic Research Laboratory, Nuffield Department of Clinical Medicine, Radcliffe Infirmary, Woodstock Road, Oxford 0X2 6HE, England

关键词: Hepatocyte;    Mitochondria;    Urea synthesis;    Enzyme location;    CO2compartmentation Cytosolic/mitochondrial pH gradient;   

DOI  :  10.1016/0014-5793(84)80998-9

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

In isolated hepatocytes the entry into urea of metabolic ¹⁴CO₂; derived from [¹⁴C] formate is modified by the addition of dichloroacetate and hydroxypyruvate. An explanation is that this results from changes in the cytoplasmic/mitochondrial pH gradient. ¹⁴CO₂, derived from [1-¹⁴C]alanine enters into urea more readily than ¹⁴CO₂ arising from [1-¹⁴C]glutamate. It is proposed that the difference, which is more than 4-fold, is indicative of a preferred pathway for metabolic CO₂ in liver mitochondria from pyruvate dehydrogenase to carbamoylphosphate synthetase than form oxoglutarate dehydrogenase. Acetazolamide inhibition of carbonic anhydrase is without effect on this observed incorporation into urea.

【 授权许可】

Unknown