Goniometer-based femtosecond crystallography with X-ray free electron lasers
Goniometer-based femtosecond crystallography with X-ray free electron lasers
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DOI：
10.1073/pnas.1418733111
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发表时间：
2014-12-02
影响因子：
11.1
通讯作者：
Hodgson, Keith O.
中科院分区：
文献类型：
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作者：
Cohen, Aina E.;Soltis, S. Michael;Hodgson, Keith O.
新兴的飞秒晶体学（FX）方法可以扩展小型辐射敏感晶体的衍射分辨率，并提供一种确定对辐射敏感的金属酶的催化精确结构的方法。为在直线加速器相干光源上使用而开发的基于测角仪的自动化仪器可以在各种样品类型上进行高效、灵活的 FX 实验。对于棒状 Cpl 氢化酶晶体，仅使用 5 个晶体和约 30 分钟的光束时间来获得 125 个静态衍射图，用于生成 1.6 埃分辨率的电子密度图。对于较小的晶体，使用高密度网格来提高样品通量；暴露了以随机方向安装在 32 个网格内的 930 个肌红蛋白晶体，证明了这种方法的实用性。 β(2)-肾上腺素受体低温冷却晶体和 RNA 聚合酶 II 复合物的筛选结果表明，对辐射非常敏感的样品的衍射分辨率有可能超出基于波荡器的同步加速器源的范围。
The emerging method of femtosecond crystallography (FX) may extend the diffraction resolution accessible from small radiationsensitive crystals and provides a means to determine catalytically accurate structures of acutely radiation-sensitive metalloenzymes. Automated goniometer-based instrumentation developed for use at the Linac Coherent Light Source enabled efficient and flexible FX experiments to be performed on a variety of sample types. In the case of rod-shaped Cpl hydrogenase crystals, only five crystals and about 30 min of beam time were used to obtain the 125 still diffraction patterns used to produce a 1.6-angstrom resolution electron densi map. For smaller crystals, high-density grids were used to increase sample throughput; 930 myoglobin crystals mounted at random orientation inside 32 grids were exposed, demonstrating the utility of this approach. Screening results from cryocooled crystals of beta(2)-adrenoreceptor and an RNA polymerase II complex indicate the potential to extend the diffraction resolution obtainable from very radiation-sensitive samples beyond that possible with undulator-based synchrotron sources.