A ligand, L, binds non-covalently to the active site of an e…

A ligand, L, binds non-covalently to the active site of an enzyme with a dissociation constant, Kd, of 1 nM. When a different type of ligand, X, is bound non-covalently to a different site in the enzyme the ligand L binds non-covalently to the active site of the enzyme with a Kd of 1 µM. The effect exerted by X on the binding of L to the enzyme is an example of: