What are the correct coenzyme forms that correspond to X and Y in the following reaction as catalyzed by lactate dehydrogenase? Pyruvate + X → Lactate + Y A)X = NADH Y = NAD⁺ B)X = NADPH Y = NADP⁺ C)X = NAD⁺ Y = NADH D)X = FAD Y = FADH₂ E)X = NADH Y = NADP⁺

Question

Quizplus · Accepted Answer

Lactate dehydrogenase catalyzes the conversion of pyruvate to lactate via the oxidation of NADH to NAD+. Therefore, X should be NADH (not NADPH or any other forms of NAD) and Y should be NAD+. The other choices are not correct because the coenzyme forms do not match the reaction catalyzed by lactate dehydrogenase.

What Are the Correct Coenzyme Forms That Correspond to X