Question

The amino acid methionine can be used as fuel by being converted to succinyl CoA. What would be the estimated ATP yield for the breakdown of methionine in this way if the succinyl CoA can then enter the citric acid cycle with no input of glucose?

Answer 1

18 molecules of ATP will be produced for the breakdown of methionine to succinyl CoA and the entry of succinyl CoA to the citric acid cycle with no input of glucose.

Step-by-step explanation:

Reactions reduced co enzymes ATP formation

α keto glutarate to propionyl CoA 2 NADH 6 moles

Succinyl CoA to succinate 2 GTP≈ 2 ATP

Succinate to fumarate 2FADH2 4 moles

Malate to oxaloacetate 2 NADH 6 moles