Question

You are studying the enzyme kinetics of enzymes in the Kreb cycle. You add a molecule to the mixture that appears to act as a competitive inhibitor of one of the enzymes. At first, you cannot tell which enzyme is inhibited, but you can tell that it is bound to the inner mitochondrial membrane. Can you guess which Kreb cycle enzyme you have inhibited and how do you know?

Answer 1

Answer: Succinate dehydrogenase

Explanation: succinate dehydrogenase or Complex II or succinate-coenzyme Q reductase is an enzyme complex involved in citric acidic cycle, bound to the inner mitochondrial membrane of mammalian mitochondria and cell membrane of many bacterial cells. It is the only enzyme that participates in both the citric acid cycle and the electron transport chain. This enzyme catalyzes the oxidation of succinate to fumarate with the reduction of ubiquinone to ubiquinol, reaction occurs in the inner mitochondrial membrane by coupling the two reactions together.