4.4 Article

Charge accumulation in electron cryomicroscopy

期刊

ULTRAMICROSCOPY
卷 187, 期 -, 页码 43-49

出版社

ELSEVIER SCIENCE BV
DOI: 10.1016/j.ultramic.2018.01.009

关键词

Low-dose electron microscopy; Single-particle reconstruction; Charging; CryoEM; Structure determination

资金

  1. Leverhulme Early Career Fellowship
  2. Medical Research Council [U105192715, U105184322]
  3. Medical Research Council [MC_UP_1201/17, MC_U105184322] Funding Source: researchfish
  4. MRC [MC_UP_1201/17, MC_U105184322] Funding Source: UKRI

向作者/读者索取更多资源

When irradiated in a transmission electron microscope, plunge-frozen, amorphous water ice specimens accumulate a pattern of static charge that changes dynamically as the specimen is irradiated, and which can deflect the transmitted electrons and blur the resultant micrographs. Here we provide a physical description of this charge accumulation and characterise its dynamic behaviour in the context of low-dose electron cryomicroscopy (cryoEM). We observe the accumulation of positive charge in the primary irradiation area as expected from earlier work. To our surprise, we also observed a build-up of negative charge in nearby unirradiated regions of the specimen. Using a standard carbon support foil containing a pure water ice specimen, we collect a portion of this negative charge in the micrometer sized specimen holes which act as electrostatic lenses. These unusual, diverging micro-lenses are extremely sensitive charge detectors that allow us to directly measure the magnitude and dynamics of charge accumulation and neutralisation that occur during cryoEM imaging. Using these measurements, we find that the build-up of charge on the specimen saturates to a dynamic equilibrium at an electron fluence which is orders of magnitude lower than required for a typical low-dose micrograph. The measurements here will guide the development of optimal imaging conditions for biological specimens and contribute to a complete theory of information loss in electron cryomicroscopy. (C) 2018 MRC Laboratory of Molecular Biology. Published by Elsevier B.V.

作者

我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。

评论

主要评分

4.4
评分不足

次要评分

新颖性
-
重要性
-
科学严谨性
-
评价这篇论文

推荐

暂无数据
暂无数据