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bioRxiv · 10.1101/2020.01.21.914507

High-resolution cryo-EM using beam-image shift at 200 keV

Cash, J. N.·Kearns, S.·Li, Y. A.·Cianfrocco, M. A.
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Abstract

Recent advances in single-particle cryo-electron microscopy (cryo-EM) data collection utilizes beam-image shift to improve throughput. Despite implementation on 300 keV cryo-EM instruments, it remains unknown how well beam-image shift data collection affects data quality on 200 keV instruments and how much aberrations can be computationally corrected. To test this, we collected and analyzed a cryo-EM dataset of aldolase at 200 keV using beam-image shift. This analysis shows that beam tilt on the instrument initially limited the resolution of aldolase to 4.9[A]. After iterative rounds of aberration correction and particle polishing in RELION, we were able to obtain a 2.8[A] structure. This analysis demonstrates that software correction of microscope aberrations can provide a significant improvement in resolution at 200 keV.

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Cash, J. N., Kearns, S., Li, Y. A., Cianfrocco, M. A.. 2020-01-21. High-resolution cryo-EM using beam-image shift at 200 keV. https://doi.org/10.1101/2020.01.21.914507

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