What is the function of ketoglutarate dehydrogenase?

Alpha-ketoglutarate dehydrogenase (α-KGDH) is a highly regulated enzyme, which could determine the metabolic flux through the Krebs cycle. It catalyses the conversion of α-ketoglutarate to succinyl-CoA and produces NADH directly providing electrons for the respiratory chain.

Where is a ketoglutarate dehydrogenase located?

Evidence is presented that the mitochondrial Krebs cycle enzyme α-ketoglutarate dehydrogenase (KGDH) is a component of the mitochondrial antioxidant system and a key sensor of redox status, altering function to induce critical changes in mitochondrial and cellular metabolism to prevent oxidative damage.

Is Alpha ketoglutarate reversible?

Oxoglutarate dehydrogenase plays a role in the cellular response to stress. The enzyme complex undergoes a stress-mediated temporary inhibition upon acute exposure to stress.

Is a ketoglutarate dehydrogenase a Multienzyme complex?

Both pyruvate and α-ketoglutarate are keto acids. Thus, the KGDC is a multienzyme complex with striking similarities to the pyruvate dehydrogenase complex. Both complexes bind an α-keto acid to a thiamine pyrophosphate coenzyme, followed by decarboxylation.

What activates a ketoglutarate dehydrogenase?

The activity of alpha-ketoglutarate dehydrogenase complex from pigeon breast muscle is controlled by ADP and the reaction products, i. e. succinyl-CoA and NADH. ADP activates the alpha-ketoglutarate dehydrogenase component of the complex, whereas NADH inhibits alpha-ketoglutarate dehydrogenase and lipoyl dehydrogenase.

What inhibits a ketoglutarate dehydrogenase?

alpha-Keto-beta-methyl-n-valeric acid (KMV) inhibits KGDHC activity in living N2a cells in a dose- and time-dependent manner. Reductions in this key mitochondrial enzyme will likely make the cells more vulnerable to metabolic insults that promote cell death.

How is alpha-ketoglutarate produced?

α-Ketoglutarate can be produced by: Oxidative decarboxylation of isocitrate by isocitrate dehydrogenase. Oxidative deamination of glutamate by glutamate dehydrogenase. From galacturonic acid by the organism Agrobacterium tumefaciens.

What causes alpha-ketoglutarate dehydrogenase deficiency?

Alpha-ketoglutarate dehydrogenase deficiency is a congenital error of an enzyme in the citric acid cycle. It is thought to be caused by low molar ratios of ketone bodies in the plasma of neonates with congenital lactic acidosis.

How is citrate synthase activated?

In the citric acid cycle, these remaining carbon atoms are fully oxidized to form carbon dioxide. Citrate synthase starts this process by taking the molecules of acetate and attaching them to oxaloacetate, which acts as a convenient handle as the carbon atoms are passed from enzyme to enzyme in the citric acid cycle.

Which compound can be used to generate α ketoglutarate?

Why is alpha ketoglutarate important?

Alpha-ketoglutarate (AKG) is a crucial intermediate of the Krebs cycle and plays a critical role in multiple metabolic processes in animals and humans. Of note, AKG contributes to the oxidation of nutrients (i.e., amino acids, glucose, fatty acids) and then provides energy for cell processes.