Which of the following is correct concerning the metabolic reaction shown below?
Pyruvate + CO₂ + ATP SYMBOL 174 \f "Symbol" oxaloacetate + ADP + P_i
(I) This metabolic reaction is catalyzed by pyruvate carboxykinase.
(II) The enzyme that catalyzes this reaction is activated by high concentrations of acetyl-CoA .
(III) The enzyme that catalyzes this reaction is covalently bonded to the coenzyme pyridoxal-5ꞌ-phosphate.
(IV) The enzyme that catalyzes this reaction is located in the endoplasmic reticulum of the cell .

Question

Quizplus · Accepted Answer

The reaction described is catalyzed by pyruvate carboxylase, not pyruvate carboxykinase. Pyruvate carboxylase is activated by high concentrations of acetyl-CoA, making statement II correct. It does not require pyridoxal-5' phosphate as a coenzyme, nor is it located in the endoplasmic reticulum; it is found in the mitochondria.

Which of the Following Is Correct Concerning the Metabolic Reaction