Chapter 13, Problem 13.42EP

Interpretation Introduction

Interpretation: To identify the fate of the third pyruvate carbon atom in the oxidation of pyruvate to acetyl CoA.

Concept introduction: Pyruvate is the end product in the glycolysis. The production of the fate of pyruvate varies with the nature of the organism and the cellular conditions. The three common fates of pyruvate are as follows:

Aerobic reactions need oxygen while anaerobic reactions don’t need oxygen. Pyruvate forms $\text{acetyl CoA}$ under oxygen-rich conditions.

Pyruvate $\left({\text{CH}}_3{\text{COCOO}}^{-}\right)$ is the conjugate base of pyruvic acid $\left({\text{CH}}_3\text{COCOOH}\right)$. Pyruvate molecule contains three carbon atoms, therefore, it is a ${\text{C}}_3$ molecule. Acetyl group $\left({\text{CH}}_3{\text{COO}}^{-}\right)$ contains two carbon atoms. Therefore, ${\text{CH}}_3{\text{COO}}^{-}$ is a ${\text{C}}_2$ molecule.