Question

phosphofructokinase is regulated by a number of factors, including high levels of atp. why is this enzyme regulated by atp levels? multiple choice if atp levels are high, this provides a mechanism to directly inhibit the citric acid cycle, thus preventing further generation of nadh, fadh₂ and atp molecules that are not needed. if atp levels are high, it is important to directly inhibit the reaction that commits the substrate to glycolysis to allow the substrate to be available for other reactions, since the cell has ample energy. if atp levels are high, it is important to inhibit atp synthase, and phosphofructokinase directly inhibits atp synthase. if atp levels are high, this provides a mechanism to directly inhibit the electron transport chain, thus preventing the formation of a proton gradient in the intermembrane space of mitochondria.

Explanation:

Phosphofructokinase is a key regulatory enzyme in glycolysis. When ATP levels are high, the cell has sufficient energy. Inhibiting the reaction that commits the substrate to glycolysis (catalyzed by phosphofructokinase) allows the substrate to be used for other processes. This is a form of negative - feedback regulation to prevent unnecessary energy production.

Answer:

If ATP levels are high, it is important to directly inhibit the reaction that commits the substrate to glycolysis to allow the substrate to be available for other reactions, since the cell has ample energy.