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Comparison of an Atomic Model and Its Cryo-EM Image at the Central Axis of a Helix.

ABSTRACT: Cryo-electron microscopy (cryo-EM) is an important biophysical technique that produces three-dimensional (3D) density maps at different resolutions. Because more and more models are being produced from cryo-EM density maps, validation of the models is becoming important. We propose a method for measuring local agreement between a model and the density map using the central axis of the helix. This method was tested using 19 helices from cryo-EM density maps between 5.5 Å and 7.2 Å resolution and 94 helices from simulated density maps. This method distinguished most of the well-fitting helices, although challenges exist for shorter helices.

SUBMITTER: He J

PROVIDER: S-EPMC4894056 | biostudies-literature | 2015 Nov

REPOSITORIES: biostudies-literature

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Comparison of an Atomic Model and Its Cryo-EM Image at the Central Axis of a Helix.

He Jing J Zeil Stephanie S Hallak Hussam H McKaig Kele K Kovacs Julio J Wriggers Willy W

Proceedings. IEEE International Conference on Bioinformatics and Biomedicine 20151101

Cryo-electron microscopy (cryo-EM) is an important biophysical technique that produces three-dimensional (3D) density maps at different resolutions. Because more and more models are being produced from cryo-EM density maps, validation of the models is becoming important. We propose a method for measuring local agreement between a model and the density map using the central axis of the helix. This method was tested using 19 helices from cryo-EM density maps between 5.5 Å and 7.2 Å resolution and ...[more]

PMID: 27280059

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