Cryotomography: Low-dose Automated Tomography of Frozen-hydrated Specimens
Electron tomography is an imaging technique that provides 3D images of a specimen with nanometer scale resolution. The range of specimens that can be investigated with this technique is particularly wide, from large (500–1000 nm) unique variable structures such as whole cells to suspensions of thousands of small identical macromolecules (>200 kDa).When applied to cryofixed frozen-hydrated biological material, the technique is often referred to as cryotomography. In combination with automated low-dose data collection and advanced computational methods, such as molecular identification based on pattern recognition, cryotomography can be used to visualize the architecture of small cells and organelles and/or to map macromolecular structures in their cellular environment. The resolution that can be obtained with cryotomography depends on several fundamental and technical issues related to specimen preparation, microscopy and subsequent image processing steps, but will typically be in the range of 5–10 nm.
KeywordsTilt Angle Specimen Holder Tilt Axis Data Collection Scheme Electron Dose
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