Fatty Acid Oxidation and Energy Production

What is the ATP yield from the breakdown of palmitate through β-oxidation and subsequent entry into the citric acid cycle?

How many mols of FADH2 are produced during the complete β-oxidation of palmitate?

What is the main pathway for fatty acids with an odd number of carbon atoms in terms of their final product?

How many mols of ATP are produced from oxidative phosphorylation for every mol of NADH + H+ generated in β-oxidation?

Which statement accurately describes the role of carnitine in fatty acid oxidation?

Determine the total number of ATP molecules formed from directly cleaved two-carbon units from palmitate without including the citric acid cycle.

Fatty Acid Oxidation

Fatty acids with less than 12 carbons can cross the inner mitochondrial membrane as acyl-CoA to undergo β-oxidation without requiring carnitine.
Fatty acids with an odd number of carbon atoms are oxidized through β-oxidation, producing acetyl CoA until a three-carbon (propionyl-CoA) residue remains, which is then converted to succinyl-CoA, a constituent of the citric acid cycle.

Energy Produced from Fatty Acid Oxidation

In β-oxidation, for every 2 carbons cleaved from an acyl-CoA molecule to produce acetyl-CoA, 1 mol of FADH2 and 1 mol of NADH + H+ are released, producing 4 mol ATP (1.5 ATP from FADH2 + 2.5 ATP from NADH + H+).
7 cycles of β-oxidation are required to break down palmitate (16 carbons) into acetyl-CoA, producing 28 mol ATP.
Each mol of acetyl-CoA produced from β-oxidation enters the citric acid cycle, producing 10 mol of ATP.
In the β-oxidation of palmitate, 8 mol of acetyl-CoA are formed, producing 80 mol ATP (8 x 10) in the citric acid cycle.
The total ATP produced per mole of palmitate undergoing oxidation is (28+80) - 2 ATP = 106 mol ATP, equivalent to 3233 kJ (106 x 30.5).

Learn about the process of fatty acid oxidation, including how shorter fatty acids can cross the mitochondrial membrane and how fatty acids with odd chain lengths are oxidized. Understand how energy is produced from fatty acid oxidation.