Which enzyme converts oxaloacetate to phosphoenolpyruvate in gluconeogenesis?
Answer and explanation
Correct answer: C. Phosphoenolpyruvate carboxykinase
- Step 1: Pyruvate is first carboxylated to oxaloacetate by pyruvate carboxylase. Step 2. PEP carboxykinase then decarboxylates and phosphorylates oxaloacetate to PEP. Answer: PEP carboxykinase. Why not the others: pyruvate carboxylase makes the oxaloacetate, and the other two enzymes act at later steps.
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