Release of succinate from succinyl-CoA can be coupled to GTP synthesis because:
A) The amide bond between succinate and CoA has a large − Δ G of hydrolysis.
B) The thioester bond between succinate and CoA has a large − Δ G of hydrolysis.
C) The link between succinate and CoA involves an acid anhydride to phosphate.
D) Coenzyme A is a "high energy" compound, just like GTP.
E) None of these explains why GTP can be formed during this reaction.

Question

Quizplus · Accepted Answer

The thioester bond between succinate and CoA has a large negative ΔG of hydrolysis, which provides the energy necessary for the synthesis of GTP from GDP and Pi in the reaction catalyzed by succinyl-CoA synthetase during the citric acid cycle.

Release of Succinate from Succinyl-CoA Can Be Coupled to GTP