Per beta-oxidation cycle, what electron carriers are produced?

Per beta-oxidation cycle, what electron carriers are produced?

• A. One FADH2 and one NADH
• B. One NADH only
• C. One FADH2 only
• D. No electron carriers

Answer: (A)

Beta-oxidation cycles involve two oxidation steps in each round. In the first oxidation, acyl-CoA dehydrogenase removes electrons and reduces FAD to FADH2. In the subsequent oxidation, beta-hydroxyacyl-CoA dehydrogenase oxidizes NAD+ to NADH. So, for every cycle, you generate both reduced cofactors: one FADH2 and one NADH. The carbon backbone is shortened by two and released as acetyl-CoA, which goes to the citric acid cycle. No other electron carriers are produced in that cycle. That’s why one FADH2 and one NADH best describes the products of each beta-oxidation cycle.

Beta-oxidation cycles involve two oxidation steps in each round. In the first oxidation, acyl-CoA dehydrogenase removes electrons and reduces FAD to FADH2. In the subsequent oxidation, beta-hydroxyacyl-CoA dehydrogenase oxidizes NAD+ to NADH. So, for every cycle, you generate both reduced cofactors: one FADH2 and one NADH. The carbon backbone is shortened by two and released as acetyl-CoA, which goes to the citric acid cycle. No other electron carriers are produced in that cycle. That’s why one FADH2 and one NADH best describes the products of each beta-oxidation cycle.