Cash Jennifer N, Kearns Sarah, Li Yilai, Cianfrocco Michael A
Life Sciences Institute, Department of Biological Chemistry, University of Michigan, Ann Arbor, MI 48109, USA.
IUCrJ. 2020 Oct 29;7(Pt 6):1179-1187. doi: 10.1107/S2052252520013482. eCollection 2020 Nov 1.
Recent advances in single-particle cryo-electron microscopy (cryo-EM) data collection utilize 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 the extent to which aberrations can be computationally corrected. To test this, a cryo-EM data set for aldolase was collected at 200 keV using beam-image shift and analyzed. This analysis shows that the instrument beam tilt and particle motion initially limited the resolution to 4.9 Å. After particle polishing and iterative rounds of aberration correction in , a 2.8 Å resolution structure could be obtained. This analysis demonstrates that software correction of microscope aberrations can provide a significant improvement in resolution at 200 keV.
单颗粒冷冻电子显微镜（cryo-EM）数据采集的最新进展利用束流图像偏移来提高通量。尽管已在300 keV冷冻电子显微镜仪器上实施，但尚不清楚束流图像偏移数据采集对200 keV仪器上的数据质量有何影响，以及像差在多大程度上可以通过计算进行校正。为了测试这一点，使用束流图像偏移在200 keV下收集了醛缩酶的冷冻电子显微镜数据集并进行分析。该分析表明，仪器束流倾斜和颗粒运动最初将分辨率限制在4.9 Å。在进行颗粒抛光和多轮像差校正后，可以获得2.8 Å分辨率的结构。该分析表明，在200 keV下，显微镜像差的软件校正可以显著提高分辨率。
