摘要
The structural information of functionally important macromolecular assemblies is a key to molecular biology and is of great interest to structural biologists.Cryo-electron microscopy(cryo-EM),particularly the single particle analysis(SPA),has been regarded as one of the three primary tech-
The structural information of functionally important mac- romolecular assemblies is a key to molecular biology and is of great interest to structural biologists. Cryo-electron mi- croscopy （cryo-EM）, particularly the single particle analysis （SPA）, has been regarded as one of the three primary tech- niques for structure determination, together with X-ray crystallography and nuclear magnetic resonance （NMR）. For single particle cryo-EM, a tiny amount （~3 μL） of puri- fied biological samples at a concentration around 0.1-2 mg mL-1 are placed onto an EM grid, blotted with a filter paper and rapidly frozen into a thin layer of vitreous ice. The EM grid with frozen samples is then transferred to a transmis- sion electron microscope for imaging.
