Figure 5.

Mechanism of protein-ligand binding reactions. An important distinction between the conformational isomerism and induced-fit mechanisms is the step in the binding mechanism at which the conformational change in the protein occurs – before the initial contact with ligand in the case of conformational isomerism, but afterward in the case of the induced-fit mechanism. The functional impact of this difference is that conformational isomerism can drive polyreactivity by providing alternative protein conformers for the binding of different antigens.