Recent developments have resulted in electron cryo-microscopy (cryo-EM) becoming a useful tool for the structure determination of biological macromolecules. For samples containing inherent flexibility, heterogeneity or preferred orientation, the collection of extensive cryo-EM data using several conditions and microscopes is often required. In such a scenario, merging cryo-EM data sets is advantageous because it allows improved three-dimensional reconstructions to be obtained. Since data sets are not always collected with the same pixel size, merging data can be challenging. Here, two methods to combine cryo-EM data are described. Both involve the calculation of a rescaling factor from independent data sets. The effects of errors in the scaling factor on the results of data merging are also estimated. The methods described here provide a guideline for cryo-EM users who wish to combine data sets from the same type of microscope and detector.

中文翻译：

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电子冷冻显微镜中合并数据集的方法。

最近的发展使得冷冻电子显微镜（cryo-EM）成为测定生物大分子结构的有用工具。对于含有固有灵活性、异质性或首选方向的样品，通常需要使用多种条件和显微镜收集大量冷冻电镜数据。在这种情况下，合并冷冻电镜数据集是有利的，因为它允许获得改进的三维重建。由于数据集并不总是以相同的像素大小收集，因此合并数据可能具有挑战性。这里描述了两种组合冷冻电镜数据的方法。两者都涉及从独立数据集计算重新缩放因子。还估计了比例因子误差对数据合并结果的影响。此处描述的方法为希望组合来自同一类型显微镜和探测器的数据集的冷冻电镜用户提供了指导。