<P> A regulatory site ( also known as an `` allosteric site '' ) is a site on an allosteric protein to which a modulator molecule ( or allosteric regulator ) binds . This ligand - binding site on a receptor or enzyme is distinct from the active site . Allosteric modulators alter enzyme activity by binding to the regulatory site . Some allosteric regulators activate enzymes , while others inhibit them . The working hypothesis is that when allosteric regulators bind to the regulatory site , the protein undergoes conformational changes which changes the enzyme 's activity . </P>
which site of an enzyme is called allosteric site
regulatory site