Structure Determination of Icosahedral Viruses Imaged by Cryo-electron Microscopy
نویسندگان
چکیده
Three-dimensional (3D) image reconstruction of icosahedral viruses by transmission electron microscopy (TEM) began with the pioneering work on negatively stained samples in Cambridge, UK. This ushered in a new era for virus structure determination and helped lay a firm foundation for subsequent, near atomic resolution X-ray crystallographic studies of viruses such as tomato bushy stunt and southern bean mosaic virus. Crowther et al.’s elegant common lines formulation was extremely laborious by today’s standards as it required hands-on inspection and analysis of images and their Fourier transforms to identify the orientations of individual virus particles on the TEM support grid. At that time, the B30 Å resolution that could be achieved was limited not by the ability to collect and analyze adequate numbers of images but rather by effects of stain, radiation damage and various distortions to the sample. The advent of single-particle cryo-electron microscopy (cryo-EM) subsequently revolutionized the use of microscopy for structure determination for
منابع مشابه
Single particle cryo-electron microscopy and 3-D reconstruction of viruses.
With fast progresses in instrumentation, image processing algorithms, and computational resources, single particle electron cryo-microscopy (cryo-EM) 3-D reconstruction of icosahedral viruses has now reached near-atomic resolutions (3-4 Å). With comparable resolutions and more predictable outcomes, cryo-EM is now considered a preferred method over X-ray crystallography for determination of atom...
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