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Hollow Cone Electron Imaging for Single Particle 3D Reconstruction of Proteins.

ABSTRACT: The main bottlenecks for high-resolution biological imaging in electron microscopy are radiation sensitivity and low contrast. The phase contrast at low spatial frequencies can be enhanced by using a large defocus but this strongly reduces the resolution. Recently, phase plates have been developed to enhance the contrast at small defocus but electrical charging remains a problem. Single particle cryo-electron microscopy is mostly used to minimize the radiation damage and to enhance the resolution of the 3D reconstructions but it requires averaging images of a massive number of individual particles. Here we present a new route to achieve the same goals by hollow cone dark field imaging using thermal diffuse scattered electrons giving about a 4 times contrast increase as compared to bright field imaging. We demonstrate the 3D reconstruction of a stained GroEL particle can yield about 13.5?Å resolution but using a strongly reduced number of images.

SUBMITTER: Tsai CY

PROVIDER: S-EPMC4904375 | biostudies-literature | 2016 Jun

REPOSITORIES: biostudies-literature

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Hollow Cone Electron Imaging for Single Particle 3D Reconstruction of Proteins.

Tsai Chun-Ying CY Chang Yuan-Chih YC Lobato Ivan I Van Dyck Dirk D Chen Fu-Rong FR

Scientific reports 20160613

The main bottlenecks for high-resolution biological imaging in electron microscopy are radiation sensitivity and low contrast. The phase contrast at low spatial frequencies can be enhanced by using a large defocus but this strongly reduces the resolution. Recently, phase plates have been developed to enhance the contrast at small defocus but electrical charging remains a problem. Single particle cryo-electron microscopy is mostly used to minimize the radiation damage and to enhance the resolutio ...[more]

PMID: 27292544

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