Equilibration of metabolic CO2 with preformed CO2 and bicarbonate

FEBS Letters

Hems, Reginald¹  Saez, Guillermo T.¹ 

[1] Metabolic Research Laboratory, Nuffield Department of Clinical Medicine, Radcliffe Infirmary, Woodstock Road, Oxford OX2 6HE, England

关键词: Urea synthesis;    Equilibration of metabolic CO2;    Carbamoylphosphate synthetase;    Mitochondrial carbonic anhydrase;    Hepatocytes;    Isotope data interpretation;   

DOI  :  10.1016/0014-5793(83)80659-0

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Entry of metabolic ¹⁴CO₂ into urea is shown to occur more readily than it equilibrates with the general pool of cellular plus extracellular bicarbonate plus CO₂. Since the sites of CO₂ production (pyruvate dehydrogenase and oxoglutarate dehydrogenase) and of fixation (carbamoylphosphate synthetase) are intramitochondrial, it is likely that the fixation of CO₂ is also more rapid than its equilibration with the cytoplasmic pool of bicarbonate plus CO₂. This observation may point to a more general problem concerning the interpretation of isotope data, when compartmentation or proximity of sites of production and utilisation of metabolites may result in the isotope following a preferred pathway.

【 授权许可】

Unknown