Question

What are the irreversible steps of the TCA cycle?

Answer 1

TCA cycle

1. The tricarboxylic acid (TCA) cycle, also known as the Krebs or citric acid cycle, is the cell's primary source of energy and an important part of aerobic respiration.
2. The cycle turns the chemical energy of acetyl coenzyme A (acetyl CoA) into the reducing power of nicotinamide adenine dinucleotide (NADH).

The TCA cycle has three irreversible steps:

1. The condensation of oxaloacetate with acetyl CoA produces citrate. Citrate synthase catalyzes the process.
2. The oxidative decarboxylation of isocitrate produces -ketoglutarate. Isocitrate dehydrogenase catalyzes the process.
3. By oxidative decarboxylation of -ketoglutarate, succinyl CoA is formed. -ketoglutarate dehydrogenase catalyzes the process.
   The figure showing Kreb's cycle is given below: