Allosteric regulation of proteins

Allostery is a mechanism by which the activity of a large number of proteins is regulated. It is manifested as a change in the activity, either ligand binding or catalysis of one site of a protein due to a ligand binding to another distinct site of the protein. The allosteric effect is transduced by a change in the structural properties of the protein. It has been traditionally understood using either the concerted MWC (Monod, Wyman and Changeux) model, or the sequential KNF (Koshland, Nemethy and Filmer) model of structural changes. However, allostery is fundamentally a thermodynamic process and requires an alteration in the enthalpy or entropy associated with the process.