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Sample preparation induced artifacts in cryo-electron tomographs.

ABSTRACT: We investigated the effects of sample preparation and of the exposure to an electron beam on particles in cryo-electron tomographs. Various virus particles with icosahedral symmetry were examined, allowing a comparison of symmetrically related components that should be identical in structure but might be affected differently by these imaging artifacts. Comparison of tomographic reconstructions with previously determined structures established by an independent method showed that neither freezing nor electron beam exposure produced a significant amount of shrinkage along the z axis (thickness). However, we observed damage to regions of the particles located close to the surface of the vitreous ice.

SUBMITTER: Plevka P

PROVIDER: S-EPMC3507990 | biostudies-literature | 2012 Oct

REPOSITORIES: biostudies-literature

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Sample preparation induced artifacts in cryo-electron tomographs.

Plevka Pavel P Battisti Anthony J AJ Winkler Dennis C DC Tars Kaspars K Holdaway Heather A HA Bator Carol M CM Rossmann Michael G MG

Microscopy and microanalysis : the official journal of Microscopy Society of America, Microbeam Analysis Society, Microscopical Society of Canada 20121008 5

We investigated the effects of sample preparation and of the exposure to an electron beam on particles in cryo-electron tomographs. Various virus particles with icosahedral symmetry were examined, allowing a comparison of symmetrically related components that should be identical in structure but might be affected differently by these imaging artifacts. Comparison of tomographic reconstructions with previously determined structures established by an independent method showed that neither freezing ...[more]

PMID: 23040048

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