An equilibrium mixture of alternate quaternary structure assemblies can form a basis for allostery. The morpheein model of allostery is a concerted dissociative model that describes an equilibrium of alternate quaternary structure assemblies whose architectures are dictated by alternate conformations in the dissociated state. Kinetic and biophysical anomalies that suggest that the morpheein model of allostery applies for a given protein of interest are briefly described. Two methods are presented for evaluating proteins as potential morpheeins. One is a subunit interchange method that uses chromatography, dialysis, and mass spectroscopy to monitor changes in multimer composition. The other is a two-dimensional native gel electrophoresis method to monitor ligand-induced changes in an equilibrium of alternate multimeric assemblies.
Keywords: Allostery, morpheein, quaternary structure equilibrium, 2d native PAGE, subunit interchange