Cryo TEM
Single partilce
This method is used to obtain high resolution 3D structure of protein complexes.
The sample (1-3 ul) applied to holey carbon grid and plnuge frozen in layer of vitreous ice that preserved the netive condition. The sample image at cryogenic temperatures by direct electron detectors (K2-Polara) or CCD (F20). The low contrast of this method limit the size of the biological sample to above ~200kDa.
The direct electron detectors increase the image contrast and with movie mode (a series of low dose images) allowed drift correction.
The data collection is done semi-automated with SerialEM and the micrographs are preprocess on-the-fly by GPU computer to get sense of the quality of the data.
full grid map
zoom in on one square
map of this squara
target holes in the map
view image
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