Answer
What citric acid cycle intermediates would accumulate in the presence of malonate? Succinate. Reason- Intermediate is a susbtance formed during a middle step of a metabolic reaction between reactants & the desired product. Citric acid cycle is a series of redox, dehydration, hydration & decarboxylation reaction. In presence of malonate, the inhibition of succinate oxidation by malonate is a well known phenomenon. Oxidation of succinate to fumarate is an integral part of the citric acid cycle oxidation, inhibitory effect of malonate upon the oxidation of any member of the cycle is the result of the inhibition of the succinate to fumarate step. Malonate is a competitive inhibitor of the enzyme succinate dehydrogenase (this enzyme catalyses the oxidation of succinate into fumarate in the citric acid cycle). Malonate binds to the active site of the enzyme without reacting & then competes with succinate which is main substrate of the enzyme. So, in the presence of malonate, succinate would accumulate in citric acid cycle.
Work Step by Step
What citric acid cycle intermediates would accumulate in the presence of malonate? Succinate. Reason- Intermediate is a susbtance formed during a middle step of a metabolic reaction between reactants & the desired product. Citric acid cycle is a series of redox, dehydration, hydration & decarboxylation reaction. In presence of malonate, the inhibition of succinate oxidation by malonate is a well known phenomenon. Oxidation of succinate to fumarate is an integral part of the citric acid cycle oxidation, inhibitory effect of malonate upon the oxidation of any member of the cycle is the result of the inhibition of the succinate to fumarate step. Malonate is a competitive inhibitor of the enzyme succinate dehydrogenase (this enzyme catalyses the oxidation of succinate into fumarate in the citric acid cycle). Malonate binds to the active site of the enzyme without reacting & then competes with succinate which is main substrate of the enzyme. So, in the presence of malonate, succinate would accumulate in citric acid cycle.
