The Regulated Enzymes of the Citric Acid Cycle Include _________

Question

The regulated enzymes of the citric acid cycle include _________.
A) Malate dehydrogenase
B) Fumarase
C) Citrate lyase
D) $\alpha$-Ketoglutarate dehydrogenase
E) Succinate thiokinase

Accepted Answer

The regulated enzymes of the citric acid cycle include those that catalyze highly exergonic (energy-releasing) steps, as these are points of regulation. Among the options, α-Ketoglutarate dehydrogenase (listed in a distorted form as "D) F1F1F1S1uf061F1F1F10-Ketoglutarate dehydrogenase") is a regulated enzyme of the citric acid cycle. It catalyzes the conversion of α-ketoglutarate to succinyl-CoA, a step that is tightly controlled due to its significant role in energy production and as a point of metabolic regulation.