冷-电磁相板图像显示出明显样本损伤的意想不到水平
Jonathan Remis1, Petar N Petrov1,2, Jessie T Zhang1,2
1Department of Physics, University of California Berkeley, Berkeley, CA 94720, USA.
bioRxiv : the preprint server for biology
|August 16, 2024
概括
化EM中的激光相位板显示了像阿波费里丁这样的标本中显著的粒子异质性. 这种增加的对比度突出显示了以前未被注意到的潜在样本损伤,使得结构变异的可视化更好.
科学领域:
- 结构生物学 结构生物学
- 生物物理学的生物物理.
- 电子显微镜电子显微镜
背景情况:
- 阿波费里丁 (apoF) 是高分辨率冷EM的标准.
- 激光相板 (LPP) 可以提高图像对比度.
- 之前的冷EM研究假设样本异质性最小.
研究的目的:
- 为了研究用LPP成像观察到的粒子对粒子的变化.
- 确定LPP是否揭示了以前未被检测到的样本异质性.
- 评估LPP对冷EM数据质量的影响.
主要方法:
- 用LPPs对阿波费里丁和 рибо二酸盐碳氧化酶/氧化酶 (rubisco) 进行成像.
- 将实验图像与计算LPP特征,射击噪声和方向的模拟进行比较.
- 使用最终重建分辨率评估样本质量.
主要成果:
- LPP成像显示,apoF和rubisco的异质性比预期的要大.
- 模拟证实,观察到的异质性不是由于LPP人工物,噪音或方向.
- 样本与以前文献中使用的样本相似.
结论:
- 观察到的异质性很可能源于在制备或净化过程中样品受损.
- 在LPP中,以前隐藏的细微结构变化很容易被发现.
- 阶段板冷EM可以在单个粒子层面上可视化生物学相关的结构异质性.
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