Chapter 20, Problem 14RE

REFLECT AND APPLY Comment on the fact that the reduction of pyruvate to lactate, catalyzed by lactate dehydrogenase, is strongly exergonic (recall this from Chapter 15), even though the standard free-energy change for the half reaction

$\text{Pyruvate}+{\text{2H}}^{+}+\text{2}{e}^{-}\to \text{ Lactate}$

is positive $\left(\Delta G°\text{'}=36.2{\text{ kJ mol}}^{-1}=8.8{\text{ kcal mol}}^{-1}\right)$, indicating an endergonic reaction.