MicroED for the study of protein–ligand interactions and the potential for drug discovery

Microcrystal electron diffraction (MicroED) is an electron cryo-microscopy (cryo-EM) technique used to determine molecular structures with crystals that are a millionth the size needed for traditional single-crystal X-ray crystallography. An exciting use of MicroED is in drug discovery and development, where it can be applied to the study of proteins and small molecule interactions, and for structure determination of natural products. The structures are then used for rational drug design and optimization. In this Perspective, we discuss the current applications of MicroED for structure determination of protein–ligand complexes and potential future applications in drug discovery. Microcrystal electron diffraction (MicroED) can determine the structure of proteins from crystals that are orders of magnitude smaller than those used by X-ray methods. Here, the application of MicroED to protein–ligand complexes is reviewed.