Evaluation of imaging plates as recording medium for images of negatively stained single particles and electron diffraction patterns of two-dimensional crystals
Evaluation of imaging plates as recording medium for images of negatively stained single particles and electron diffraction patterns of two-dimensional crystals
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DOI：
10.1093/jmicro/dfp036
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发表时间：
2010-02-01
期刊：
影响因子：
--
通讯作者：
Walz, Thomas
中科院分区：
文献类型：
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作者：
Li, Zongli;Hite, Richard K.;Walz, Thomas
我们评估了成像板（IP）和DITABIS微米扫描仪用于记录负染色的单颗粒标本和二维晶体的电子衍射图案的图像。我们首先建立了最佳的成像和读出条件的负染色的单颗粒标本的图像使用的图像的信噪比作为评价标准。我们发现，图像最好以67 000 x的放大率记录在IP上，以20 000的增益设置和30%的激光功率设置读出，随后在2 x 2像素上合并。我们的研究结果表明，对于负染色标本的图像，其分辨率被限制为类似于20 A，IP是EM胶片的一个很好的替代品。我们还比较了IP与2K × 2K Gatan电荷耦合器件（CCD）相机用于记录糖嵌入的二维晶体的电子衍射图案。在IP上和用CCD相机记录的水通道蛋白-0的衍射图案显示超过3 A的反射，并且具有类似的R-Friedel以及R-merge值。因此，IP可以用来收集衍射图案，但CCD相机更方便，仍然是记录电子衍射图案的最佳选择。
We evaluated imaging plates (IPs) and the DITABIS Micron scanner for their use in recording images of negatively stained single-particle specimens and electron diffraction patterns of two-dimensional crystals. We first established the optimal imaging and read-out conditions for images of negatively stained single-particle specimens using the signal-to-noise ratio of the images as the evaluation criterion. We found that images were best recorded on IPs at a magnification of 67 000x, read out with a gain setting of 20 000 and a laser power setting of 30% with subsequent binning over 2 x 2 pixels. Our results show that for images of negatively stained specimens, for which the resolution is limited to similar to 20 A, IPs are a good alternative to EM film. We also compared IPs with a 2K x 2K Gatan charge-coupled device (CCD) camera for their use in recording electron diffraction patterns of sugar-embedded two-dimensional crystals. Diffraction patterns of aquaporin-0 recorded on IPs and with the CCD camera showed reflections beyond 3 A and had similar R-Friedel as well as R-merge values. IPs can thus be used to collect diffraction patterns, but CCD cameras are more convenient and remain the best option for recording electron diffraction patterns.