Question

1. 2,4-Dinitrophenol (DNP) is a molecule that can shuttle protons across cellular membranes and was used in diet pills in the 1930s (but was quickly discontinued for its lethality). Explain how this molecule might induce weight loss, and why its consumption is often fatal.

2. Biosynthesis and breakdown of glucose share many common enzymes and reactions, but this is not the case in the metabolism of fatty acids. Compare and contrast fatty acid biosynthesis vs. beta-oxidation (location, acyl group carriers, redox cofactors, hydroxyacyl stereochemistry, C₂ unit donors/acceptors, etc.).

3. Describe in detail the route of electron flow from NADH to oxygen that establishes a proton gradient across the inner mitochondrial membrane.

4. How might a pathogenic mutation in the mitochondrial genome disrupt glycolysis and the pentose phosphate pathway?

5. When the F₁ portion of the ATP synthase complex is removed from the mitochondrial membrane and studied in solution, it functions as an ATPase. Why does it not function as an ATP synthase?

Answer 1