Receptor dynamics in molecular recognition by Cryo-EM and molecular simulation.

The appropriate selection of initial receptor structure has been the 'cornerstone' or foundation of successful structure-based virtual screening (SBVS), and plagued the structure-based design with a significantly practical problem to determine the major physiological states or important transition states of receptors (e.g. proteins with multiple low-energy conformations and ligand-dependent conformational dynamics). It is well known that current SBVS methods lack capacity to capture and characterize the intrinsic receptor flexibility with ideal cost-effectiveness. In recent years, cryoelectron microscopy (cryo-EM) has been routinely applied in the determination of biomolecular assemblies within physiological state. In this work, we review the roles of cryo-EM and ensemble docking methods to present the intrinsically dynamic behavior of biomacromolecules, as well as the ever-improving estimation of ligand binding affinities and receptor-ligand thermodynamics. Finally, we also provide an attitude for the further researches on the modeling receptor dynamics.