Enzyme

Inhibitors diminish the activity of an enzyme by altering the way substrates bind. Inhibitor structure may be similar to the substrate, but they react very slowly or not at all. Chemically, inhibitors may be large organic molecules, small molecules or ions. They are important because they can be useful for chemotherapeutic treatment of disease, and for providing experimental insights into the mechanism of enzyme action. Inhibitors work in either a reversible or an irreversible manner. Irreversible inhibition is characterized by extremely tight or covalent interaction with the enzyme, resulting in very slow dissociation and inactivation. Reversible inhibition is displayed by rapid dissociation of the inhibitor from the enzyme. There are three main classes of reversible inhibition, competitive inhibition, noncompetitive inhibition, and mixed inhibition. They are distinguishable by how they bind to enzymes and response to increasing substrate concentration. Enzyme inhibition is studied by examining reaction rates and how rates change in response to changes in experimental parameters.