Question

regarding the reaction pathway of the citric acid cycle :

In terms of overall potential energy production (ATP, GTP), how energy can be produced from one iteration of the citric acid cycle assuming all the glycolysis products from one molecule of glucose enter the cycle?

Answer 1

In the glycolysis process, one molecule of glucose produces two molecules of pyruvic acid or pyruvate. These pyruvate are than converted into acetyl - Co -A, which enters the citric acid cycle. In one complete cycle, one molecule of GTP ( form of ATP) (potential energy), three NADH and one molecule of FADH2 results. As two molecules of Acetyl- Co A ( converted form of pyruvate) are produced from one molecule of glucose during glycolysis, hence two molecules of Acetyl-CoA enters the citric acid separately, which inturns results in running of the citric acid cycle for twice. So from one molecule of glucose, 2 GTP (ATP) are produced in citric acid cycle along with 6 molecules of NADH and two molecules of FADH2.