Succinate dehydrogenase catalyzes the conversion of succinate to fumarate. The reaction is inhibited by malonic acid, which resembles succinate but cannot be acted upon by succinate dehydrogenase. Increasing the ratio of succinate to malonic acid reduces the inhibitory effect of malonic acid. What is malonic acid's role with respect to succinate dehydrogenase? Malonic acid

Here malonic acid acts as a competitive inhibitor of succinate dehydrogenase

Explanation:

Malonic acid structurally resembles succinic acid as a result the enzyme succinate dehydrogenase cannot distinguish between malonic acid and succinic acid.

That"s why malonic acid interact with succinate dehydrogenase thereby blocking the catalytic activity of the later.

As this mechanism is a type of competitive inhibition that"s why increasing the concentration of substrate succinic acid can reduce the inhibitory effect of malonic acid.