The conversion of 3-hydroxybutyrate to two molecules of acetyl-CoA produces 1 NADH and consumes 1 equivalent of ATP. What is the net ATP yield from the complete oxidation of 3-hydroxybutyrate?

Question

Quizplus · Accepted Answer

The complete oxidation of 3-hydroxybutyrate involves its conversion to two acetyl-CoA molecules. Each acetyl-CoA enters the citric acid cycle, producing 3 NADH, 1 FADH2, and 1 GTP (equivalent to ATP). Thus, two acetyl-CoA yield 6 NADH, 2 FADH2, and 2 ATP. Each NADH produces about 2.5 ATP, and each FADH2 produces about 1.5 ATP. Therefore, the total ATP yield is (6 NADH x 2.5) + (2 FADH2 x 1.5) + 2 ATP = 15 + 3 + 2 = 20 ATP. Including the 1 NADH from the conversion of 3-hydroxybutyrate (2.5 ATP) and subtracting the 1 ATP consumed, the net yield is 20 + 2.5 - 1 = 21.5 ATP.

The Conversion of 3-Hydroxybutyrate to Two Molecules of Acetyl-CoA Produces