Abstract: Single-particle cryo-electron microscopy (cryo-EM) emerged as a tool to study structures of biological macromolecules (especially large complexes) ~30 years ago. Recently, due to the newly development of high-resolution imaging device and image processing methods, huge improvement in resolution has been achieved by cryo-EM single particle analysis. Nowadays it is possible to establish atomic or near-atomic structure models of lots of biological macromolecules with cryo-EM 3D reconstruction. As a result of this so-called revolutionary breakthrough, cryo-EM has been developing into a mainstream technique of structural biology in the last few years. This work introduces cryo-EM single-particle analysis of biological macromolecules and the new breakthrough in brief, and the future development is discussed as well.

Key words: cryo-EM, single particle, 3D reconstruction, protein structure