What are the metabolic fates of pyruvate in yeast?

In yeast, the primary metabolic fate of pyruvate under anaerobic conditions is alcoholic fermentation. In this process, pyruvate is decarboxylated to produce acetaldehyde, which is then reduced to ethanol by the enzyme alcohol dehydrogenase. This conversion also regenerates NAD+, which is necessary for glycolysis to continue. In the presence of oxygen, yeast cells may also utilize aerobic respiration, where pyruvate is converted into acetyl-CoA and enters the citric acid cycle for further ATP production.