著者

米倉 功治

出版者

日本結晶学会

雑誌

日本結晶学会誌 (ISSN:03694585)

巻号頁・発行日

vol.63, no.3, pp.189-196, 2021-08-31 (Released:2021-09-02)

参考文献数

49

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The scattering powers of electron and X-ray differ by 4 - 5 orders of magnitude. Thanks to this property, the electron beam yields high-resolution diffraction spots from undersized crystals of various samples, which are hard to grow to a suitable size for X-ray diffraction even with a high-intensity synchrotron radiation beam. Thus, the technique known as electron 3D crystallography/3D ED/MicroED is recognized as being important especially in synthetic chemistry, material sciences and related areas, while single particle analysis can be used for larger-sized proteins. Here I review this technology including our recent developments and results.

著者

米倉 功治 眞木 さおり

出版者

日本結晶学会

雑誌

日本結晶学会誌 (ISSN:03694585)

巻号頁・発行日

vol.59, no.2-3, pp.88-95, 2017-06-30 (Released:2017-07-01)

参考文献数

41

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Electron 3D crystallography is a useful method for structure analysis from tiny and thin crystals of membrane proteins and protein complexes, which often yield crystals too small or too thin for even the synchrotron X-ray beam and X-ray free electron laser. More importantly, it can visualize the charged states of amino-acid residues and metals, as the diffraction pattern formed by elastically scattered electrons is directly related to the distribution of Coulomb potential. Here we introduce the development of this technique and structure determination with charges, and discuss further applications including a suitable treatment of electron scattering factors of charged atoms.

著者

米倉 功治

出版者

日本結晶学会

雑誌

日本結晶学会誌 (ISSN:03694585)

巻号頁・発行日

vol.52, no.1, pp.56-61, 2010-02-28 (Released:2011-02-25)

参考文献数

29

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There are many huge macromolecular complexes in living organisms. They are often hard to crystallize because of their size, complexity and heterogeneity. Cryo-electron microscopy (cryo-EM) is a suitable method to analyze the structures of such biological macromolecules, because it can be applied to various forms of samples, e.g. two-dimensional crystal, helical assembly, spherical virus, dispersed particle, cell organelle and cell, although attainable resolution depends on the system. In this review, I introduce these techniques and examples of the structure analysis, and briefly review the perspective of cryo-EM.