The binding of a compound to an enzyme is observed to slow down or stop the rate of the reaction catalyzed by the enzyme. Increasing the substrate concentration reduces the inhibitory effects of this compound. Which of the following could account for this observation?

a) The compound reduces disulfide bonds, causing the enzyme molecules to partially unfold.

b) The compound causes a cofactor to be lost from the enzyme.

c) The compound forms a covalent bond with one of the amino acid residues needed for enzyme activity.

d) The compound is a negative allosteric regulator.

e) The compound is a competitive inhibitor.

The correct answer is e. The compound is a competitive inhibitor.

Explanation:

An enzyme is a biologic catalyzer, it means a macromolecule that facilitates the occurrence of a particular reaction (conversion of reactants to products).

The rate at which an enzyme catalyze a reaction is affected by other compounds that interferes in the enzyme activity, leading to different degrees of inhibition, that can be reversible or irreversible. In the case of reversible inhibition, when there is a change in a condition, the activity of the enzyme and the rate of reaction are reestablished. A competitive inhibitor is a compound that competes with the enzyme for the substrate, causing a rate reduction. When you increase the amount of substrate, the activity and rate at which the enzyme usually acts, is reestablished.