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Pushing the resolution limit by correcting the Ewald sphere effect in single-particle Cryo-EM reconstructions.

ABSTRACT: The Ewald sphere effect is generally neglected when using the Central Projection Theorem for cryo electron microscopy single-particle reconstructions. This can reduce the resolution of a reconstruction. Here we estimate the attainable resolution and report a "block-based" reconstruction method for extending the resolution limit. We find the Ewald sphere effect limits the resolution of large objects, especially large viruses. After processing two real datasets of large viruses, we show that our procedure can extend the resolution for both datasets and can accommodate the flexibility associated with large protein complexes.

SUBMITTER: Zhu D

PROVIDER: S-EPMC5908801 | biostudies-literature | 2018 Apr

REPOSITORIES: biostudies-literature

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Pushing the resolution limit by correcting the Ewald sphere effect in single-particle Cryo-EM reconstructions.

Zhu Dongjie D Wang Xiangxi X Fang Qianglin Q Van Etten James L JL Rossmann Michael G MG Rao Zihe Z Zhang Xinzheng X

Nature communications 20180419 1

The Ewald sphere effect is generally neglected when using the Central Projection Theorem for cryo electron microscopy single-particle reconstructions. This can reduce the resolution of a reconstruction. Here we estimate the attainable resolution and report a "block-based" reconstruction method for extending the resolution limit. We find the Ewald sphere effect limits the resolution of large objects, especially large viruses. After processing two real datasets of large viruses, we show that our p ...[more]

PMID: 29674632

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