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Reducing effects of particle adsorption to the air-water interface in cryo-EM.

ABSTRACT: Most protein particles prepared in vitreous ice for single-particle cryo-electron microscopy (cryo-EM) are adsorbed to air-water or substrate-water interfaces, which can cause the particles to adopt preferred orientations. By using a rapid plunge-freezing robot and nanowire grids, we were able to reduce some of the deleterious effects of the air-water interface by decreasing the dwell time of particles in thin liquid films. We demonstrated this by using single-particle cryo-EM and cryo-electron tomography (cryo-ET) to examine hemagglutinin, insulin receptor complex, and apoferritin.

SUBMITTER: Noble AJ

PROVIDER: S-EPMC6168394 | biostudies-literature | 2018 Oct

REPOSITORIES: biostudies-literature

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Reducing effects of particle adsorption to the air-water interface in cryo-EM.

Noble Alex J AJ Wei Hui H Dandey Venkata P VP Zhang Zhening Z Tan Yong Zi YZ Potter Clinton S CS Carragher Bridget B

Nature methods 20180924 10

Most protein particles prepared in vitreous ice for single-particle cryo-electron microscopy (cryo-EM) are adsorbed to air-water or substrate-water interfaces, which can cause the particles to adopt preferred orientations. By using a rapid plunge-freezing robot and nanowire grids, we were able to reduce some of the deleterious effects of the air-water interface by decreasing the dwell time of particles in thin liquid films. We demonstrated this by using single-particle cryo-EM and cryo-electron ...[more]

PMID: 30250056

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