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High-resolution cryo-EM reconstructions in the presence of substantial aberrations.

ABSTRACT: Here, an analysis is performed of how uncorrected antisymmetric aberrations, such as coma and trefoil, affect cryo-EM single-particle reconstruction (SPR) results, and an analytical formula quantifying information loss owing to their presence is inferred that explains why Fourier-shell coefficient-based statistics may report significantly overestimated resolution if these aberrations are not fully corrected. The analysis is validated with reference-based aberration refinement for two cryo-EM SPR data sets acquired with a 200?kV microscope in the presence of coma exceeding 40?µm, and 2.3 and 2.7?Å reconstructions for 144 and 173?kDa particles, respectively, were obtained. The results provide a description of an efficient approach for assessing information loss in cryo-EM SPR data acquired in the presence of higher order aberrations, and address inconsistent guidelines regarding the level of aberrations that is acceptable in cryo-EM SPR experiments.

SUBMITTER: Bromberg R

PROVIDER: S-EPMC7201289 | biostudies-literature | 2020 May

REPOSITORIES: biostudies-literature

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High-resolution cryo-EM reconstructions in the presence of substantial aberrations.

Bromberg Raquel R Guo Yirui Y Borek Dominika D Otwinowski Zbyszek Z

IUCrJ 20200326 Pt 3

Here, an analysis is performed of how uncorrected antisymmetric aberrations, such as coma and trefoil, affect cryo-EM single-particle reconstruction (SPR) results, and an analytical formula quantifying information loss owing to their presence is inferred that explains why Fourier-shell coefficient-based statistics may report significantly overestimated resolution if these aberrations are not fully corrected. The analysis is validated with reference-based aberration refinement for two cryo-EM SPR ...[more]

PMID: 32431828

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