title: A group of thermodynamic potentials applicable to ligand binding by a polyfunctional macromolecule.
abstract: The binding of ligands by a macromolecule can be well described by a group of potentials derivable from the energy and of which the original binding potential is one. The group is Abelian and is isomorphic with a group of symmetries. Each member corresponds to a particular set of experimental conditions--system open to some, closed to others, of the ligand-and the group as a whole is an immediate source of all possible linkage relations applicable to the macromolecule. Seen in terms of information theory it can be interpreted as a program for the response of the macromolecule to its ligands according to the conditions with which it is faced. The group provides a ready formulation of the effect of a ligand on the equilibrium constant for a reaction involving a set of macromolecules, and it leads to a clear-cut distinction between true and pseudolinkage.
mesh_terms: D001665:Binding Sites; D007700:Kinetics; D008024:Ligands; D008433:Mathematics; D008954:Models, Biological; D011108:Polymers; D011199:Potentiometry; D013816:Thermodynamics
chemical_list: D008024:Ligands; D011108:Polymers