单颗粒冷电子显微镜具有增强的200kV冷TEM配置,可以达到接近原子分辨率
bioRxiv : the preprint server for biology
|May 20, 2024
概括
一个具有先进探测器的200kV Glacios冷电子显微镜 (cryo-EM) 实现了与300kV系统相比较的高分辨率结构. 这种具有成本效益的设置适用于各种蛋白质和核酸点.
科学领域:
- 结构生物学 结构生物学
- 生物物理学的生物物理.
- 生物化学 生物化学
背景情况:
- 单颗粒冷电子显微镜 (cryo-EM) 是一种用于确定生物分子结构的强大技术.
- 高分辨率的冷EM数据通常使用300kV的冷传输电子显微镜 (cryo-TEMs) 来获取.
- 需要具有成本效益的冷EM解决方案,可以实现高分辨率.
研究的目的:
- 系统地评估使用猎4探测器和Selectris能量波器 (Glacios-F4-S) 的200kV Glacios冷TEM的性能.
- 为了比较Glacios-F4-S上的数据收集软件性能.
- 为了评估Glacios-F4-S的分辨率能力与300kV冷TEM对各种生物样本进行比较.
主要方法:
- 使用子肌肉阿尔多酶作为SerialEM,Leginon和EPU软件的基准样本进行性能评估.
- 在Glacios-F4-S和300kV的Titan Krios cryo-TEM上对人类核细胞核粒的比较结构确定.
- 使用Glacios-F4-S.小数据集对人类RAD51对应物复合体 (BCDX2) 的分析.
主要成果:
- 所有测试的数据收集软件 (SerialEM,Leginon,EPU) 在Glacios-F4-S上的子肌肉阿尔多酶的2.6 Å分辨率重建结果都相当.
- 格拉西奥斯-F4-S获得了2.8 Å的人类核细胞核粒的名义分辨率,与300 kV的泰坦克里奥斯获得的2.5 Å相比.
- 从一个小的数据集 (≤1,000微图) 中获得了BCDX2复合物的3.3 Å重建,解析了结合的连接体.
结论:
- 格拉西奥斯-F4-S是一款具有成本效益和高性能的冷EM系统,用于高分辨率的结构生物学.
- 这种200kV的配置提供了与各种宏分子复合体的300kV冷TEM相匹配的数据质量.
- 该系统适用于需要确定新型结构的学术和工业研究人员.
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