A 56-year-old chronic alcoholic has been brought to the emergency room in a semiconscious state. Blood biochemistry reveals hypoglycemia with a blood glucose level of 45 mg/dL. Which of the following intermediates of TCA cycle can be directly converted to phosphoenolpyruvate to trigger the pathway of gluconeogenesis?

Question

Quizplus · Accepted Answer

Oxaloacetate is the TCA cycle intermediate that can be directly converted to phosphoenolpyruvate by the enzyme phosphoenolpyruvate carboxykinase in the gluconeogenesis pathway.  The TCA cycle compound, oxaloacetate, serves as a key intermediate in gluconeogenesis. Within the mitochondria, it can be converted to phosphoenolpyruvate (PEP) via the action of PEP carboxykinase.

A 56-Year-Old Chronic Alcoholic Has Been Brought to the Emergency