You are studying a cell line in which gluconeogenesis is unaffected by changes in the level of acetylCoA. These cells most likely harbor an enzyme that has lost its allosteric binding site for acetyl-CoA. Which of the following enzymes is the candidate mutated-enzyme?
A) phosphoenolpyruvate carboxykinase
B) phosphoglycerate kinase
C) phosphoglycerate mutase
D) pyruvate carboxylase
E) pyruvate kinase

Question

Quizplus · Accepted Answer

Pyruvate carboxylase is an enzyme in gluconeogenesis that is allosterically activated by acetyl-CoA. If gluconeogenesis is unaffected by acetyl-CoA levels, it suggests a mutation in pyruvate carboxylase affecting its allosteric site.  Pyruvate carboxylase activity is absolutely dependent on allosteric activation by acetyl-CoA. Therefore, this must be the affected enzyme in these cells

You Are Studying a Cell Line in Which Gluconeogenesis Is