Chapter 13, Problem 13.41EP

Interpretation Introduction

Interpretation: To identify the fate of the third pyruvate carbon atom in ethanol fermentation.

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. The fermentation process is an alternative method that oxidized NADH to ${\text{NAD}}^{+}$ under anaerobic 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. Ethanol $\left({\text{CH}}_3{\text{CH}}_2\text{OH}\right)$ contains two carbon atoms. Therefore, it is a ${\text{C}}_2$ molecule.