Explore chapters and articles related to this topic
Physical Methods for Characterizing Solids
Published in Elaine A. Moore, Lesley E. Smart, Solid State Chemistry, 2020
Cryogenic electron microscopy, or Cryo EM, is transmission electron microscopy at low temperatures. Up to 20 years ago, this simply meant freezing solids to lower temperatures in order to decrease the signal-to-noise ratio. Recently, however, this term is mainly used to describe a technique which enables the structure determination of large biological molecules such as proteins, viruses, or enzymes by the use of electron microscopy without the need of crystallisation. The development of Cryo EM by J. Dubochet, J. Frank, and R. Henderson was awarded with the Nobel Prize in Chemistry in 2017. The discovery is groundbreaking in the field of structural chemistry, simply because structural elucidation on atomic scale or resolution had only been possible by carrying out diffraction experiments on crystalline samples. Macromolecules such as proteins or enzymes are very difficult to crystallise and thus, often the structure determination of some of these compounds was not possible because single crystals of sufficient size and quality could not be grown.
A comprehensive review on stability of therapeutic proteins treated by freeze-drying: induced stresses and stabilization mechanisms involved in processing
Published in Drying Technology, 2022
Zhe Wang, Linlin Li, Guangyue Ren, Xu Duan, Jingfang Guo, Wenchao Liu, Yuan Ang, Lewen Zhu, Xing Ren
Since Cryogenic electron microscopy (Cryo-EM) was awarded the Nobel Prize in 2017, Cryo-EM technology used to analyze the molecular structure of biological macromolecules has attracted much attention. Cryo-EM analysis has become a trend, and will gradually shoulder or eventually exceed the crystal diffraction technology, which plays a great role in drug research and development. Compared with crystal diffraction technology, Cryo-EM does not require protein crystallization. By preserving samples at low temperatures, Cryo-EM can store samples in high vacuum and provide certain protection against the effects of radiation damage.[90] Moreover, protein macromolecules were resolved in a state close to the natural water solution, and the structure was more realistic. Yin et al [91] used cryo-EM to elucidate the structure of the agonist-bound activated DRD2-Gi complex, which was reorganized into a phospholipid membrane.