And both of these points are allosteric enzymes used by the steps of the citric acid cycle, the TCA cycle. So let's quickly remember the eight different steps. In step one, we take the four carbon oxaloacetate, combined with the acetyl group of acetoco enzyme A to form a six carbon molecule known as citrate. The citrate is then transformed into isocytrate, another six carbon molecule, which is basically an isomer to citrate. The isocitrate that undergoes step three, that is catalyzed by an allosteric enzyme known as isocytrate, dehydrogenase, and that produces alpha key to glutarate. The alpha key to glutrate, then catalyzed by an enzyme known as alpha key to glutarate, dehydrogenase undergoes step four and other oxidative decarboxylation step to produce a C four molecule, a four carbon molecule known as succinl coenzyme A.