Isocitraatti

Isocitraatti is an isomer of citrate, a key intermediate in the citric acid cycle. The citric acid cycle, also known as the Krebs cycle or TCA cycle, is a series of chemical reactions used by all aerobic organisms to generate energy through the oxidation of acetyl-CoA derived from carbohydrates, fats, and proteins. Isocitrate is formed from citrate by the enzyme aconitase. Specifically, aconitase catalyzes the isomerization of citrate to isocitrate. This reaction involves the removal of a water molecule from citrate and the subsequent addition of a water molecule at a different position. Isocitrate is then further processed in the citric acid cycle. It is oxidized by isocitrate dehydrogenase, a crucial regulatory enzyme in the cycle, to produce alpha-ketoglutarate, carbon dioxide, and NADH. This step is often considered a rate-limiting step of the citric acid cycle and is an important point of regulation. Genetic defects affecting isocitrate dehydrogenase can lead to various metabolic disorders.