isocitrate dehydrogenase
Quick Summary
Isocitrate dehydrogenase is an enzyme that plays a crucial role in the tricarboxylic acid (TCA) cycle, a key part of cellular respiration. This cycle breaks down fuel molecules like glucose and fatty acids into carbon dioxide and energy.1
Isocitrate dehydrogenase catalyzes the oxidation of isocitrate to alpha-ketoglutarate, releasing carbon dioxide and reducing coenzymes like NAD+ or NADP+. Some forms of this enzyme are regulated by the cell's energy state, being activated by ADP or AMP and inhibited by ATP. This regulation helps control the flow of nutrients through metabolic pathways, ensuring energy production is balanced with the cell's needs.23
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metabolismFormation of coenzyme A, carbon dioxide, and reducing equivalent…the enzyme controlling this reaction, isocitrate dehydrogenase, differs in specificity for the coenzymes; various forms occur not only in different organisms but even within the same cell. In [40] NAD(P)+ indicates that either NAD+ or NADP+ can act as a hydrogen acceptor.
Read More…the enzyme controlling this reaction, isocitrate dehydrogenase, differs in specificity for the coenzymes; various forms occur not only in different organisms but even within the same cell. In [40] NAD(P)+ indicates that either NAD+ or NADP+ can act as a hydrogen acceptor.
Read More- metabolismEnergy state of the cell
Some forms of isocitrate dehydrogenase are maximally active only in the presence of ADP or AMP and are inhibited by ATP. This is an example of regulation by covalent modification of an enzyme since the action of ATP here is to phosphorylate, and consequently to inactivate, the isocitrate…
Read MoreSome forms of isocitrate dehydrogenase are maximally active only in the presence of ADP or AMP and are inhibited by ATP. This is an example of regulation by covalent modification of an enzyme since the action of ATP here is to phosphorylate, and consequently to inactivate, the isocitrate…
Read More