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A simple and robust procedure for preparing graphene-oxide cryo-EM grids.

ABSTRACT: Graphene oxide (GO) sheets have been used successfully as a supporting substrate film in several recent cryogenic electron-microscopy (cryo-EM) studies of challenging biological macromolecules. However, difficulties in preparing GO-covered holey carbon EM grids have limited their widespread use. Here, we report a simple and robust method for covering holey carbon EM grids with GO sheets and demonstrate that these grids can be used for high-resolution single particle cryo-EM. GO substrates adhere macromolecules, allowing cryo-EM grid preparation with lower specimen concentrations and provide partial protection from the air-water interface. Additionally, the signal of the GO lattice beneath the frozen-hydrated specimen can be discerned in many motion-corrected micrographs, providing a high-resolution fiducial for evaluating beam-induced motion correction.

SUBMITTER: Palovcak E

PROVIDER: S-EPMC6119484 | biostudies-literature | 2018 Oct

REPOSITORIES: biostudies-literature

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A simple and robust procedure for preparing graphene-oxide cryo-EM grids.

Palovcak Eugene E Wang Feng F Zheng Shawn Q SQ Yu Zanlin Z Li Sam S Betegon Miguel M Bulkley David D Agard David A DA Cheng Yifan Y

Journal of structural biology 20180711 1

Graphene oxide (GO) sheets have been used successfully as a supporting substrate film in several recent cryogenic electron-microscopy (cryo-EM) studies of challenging biological macromolecules. However, difficulties in preparing GO-covered holey carbon EM grids have limited their widespread use. Here, we report a simple and robust method for covering holey carbon EM grids with GO sheets and demonstrate that these grids can be used for high-resolution single particle cryo-EM. GO substrates adhere ...[more]

PMID: 30017701

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