A computational method was developed to recover the three-dimensional coordinates of gold nanoparticles specifically attached to a protein complex from tilt-pair images collected by electron microscopy. The program was tested on a simulated dataset and applied to a real dataset comprising tilt-pair images recorded by cryo electron microscopy of RNA polymerase II in a complex with four gold-labeled single-chain antibody fragments. The positions of the gold nanoparticles were determined, and comparison of the coordinates among the tetrameric particles revealed the range of motion within the protein complexes.

中文翻译：

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金纳米粒子和倾斜对通过低温电子显微镜评估蛋白质的灵活性

开发了一种计算方法，用于从电子显微镜收集的倾斜对图像中恢复专门附着在蛋白质复合物上的金纳米粒子的三维坐标。该程序在模拟数据集上进行了测试，并应用于真实数据集，该数据集包括通过冷冻电子显微镜记录的 RNA 聚合酶 II 在具有四个金标记单链抗体片段的复合物中的倾斜对图像。金纳米粒子的位置被确定，四聚体粒子之间的坐标比较揭示了蛋白质复合物中的运动范围。