Question

List 3 potential metabolic "fates" of pyruvate OR glucose-6-phosphate. Indicate the metabolic environment associated with each fate (i.e. catabolic/ATP producing/anabolic/etc)

Answer 1

ATP production and catabolism:

A. Glycolysis B. Aerobic respiration

Carbohydrates like glucose and fructose are converted into pyruvate which is a simpler form of catabolism of sugars. ATP is also generated along the pathway. Pyruvate is an intermediate that can enter into multiple metabolic pathways, Majority of pyruvate is converted to acetyl-CoA and enters into the citric acid cycle in the mitochondria. The most important product of citric acid cycle is NADH, which is made from NAD+ as the acetyl-CoA. In anaerobic conditions of glycolysis pyruvate is converted to lactate, with the enzyme lactate dehydrogenase re-oxidizing NADH to NAD+ that can further recycle to glycolysis.

Anabolism

C. Gluconeogenesis

Glucose is made from pyruvate by the process called gluconeogenesis. Gluconeogenesis converts pyruvate to glucose-6-phosphate through a series of intermediates, many of which are shared with glycolysis. And thus it follows a reverse pathway of glycolysis .