Studies of the Mechanism of Action of Adenylosuccinase

Studies of the inhibition of yeast adenylosuccinase by the products of the reaction it catalyzes, as well as studies of the ability of the products to protect the enzyme from inhibitors, indicate that fumarate leaves the enzyme before adenylic acid. Evidence to be presented indicates that the binding of adenylic acid to the enzyme is by the phosphate group and either the amino group or the purine ring. Evidence is also cited for the existence of a sulphydryl group at the active center of the enzyme, apparently close to the C–N bond that is cleaved by the enzyme.