Single particle cryo-electron microscopy
This technique requires the collection of a large number of movies from mono-disperse protein complexes or viruses such that their 3D structure can be determined. The Titan Krios and Polara microscopes are equipped with direct electron detectors and automated data collection software that allow a large number of movies to be collected from single particle samples. The type of single particles that can be imaged range from small protein complexes (150 kDa) to large viruses (2 MDa). For proteins smaller than 150 kDa the use of the Volta phase plate may be required.
Molecular cryo-electron tomography
This technique can be used with single particle samples and is excellent at generating initial models for single particle analysis or for analysing repeating structures in larger pleomorphic objects. Tilt series are collected at areas of interest, which can then be aligned and reconstructed to generate 3D volumes. For thicker specimens zero-loss imaging is recommended.
Cellular cryo-electron tomography
This technique is used to look at large pleomorphic objects such as vesicles, isolated organelles, bacteria, and intact eukaryotic cells. Tilt series are collected at areas of interest which can then be aligned and reconstructed to generate 3D volumes. For thicker specimens zero-loss imaging is recommended and a maximum sample thickness is of 0.5 um is advised.
Electron crystallography (coming soon)
This technique requires thin 3D crystals or 2D crystals of lipid-embedded membrane proteins. For thin 3D crystals, electron diffraction data are collected. For 2D crystals, both projection images and electron diffraction data (if feasible) are collected and then combined to generate a 3D reconstruction of the protein of interest.
Focussed Ion Beam Milling and Imaging (coming soon)
This technique uses the Scios DualBeam Scanning Electron Microscope (SEM) and Focused Ion Beam (FIB) system to enable precision milling of frozen-hydrated samples. The primary use of this instrument will be to generate thin lamellae of cellular samples for cryo-electron tomography.
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