An advanced workflow for single-particle imaging with the limited data at an X-ray free-electron laser.
An advanced workflow for single-particle imaging with the limited data at an X-ray free-electron laser.
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DOI：
10.1107/s2052252520012798
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发表时间：
2020-11-01
期刊：
影响因子：
3.9
通讯作者：
Vartanyants IA
中科院分区：
文献类型：
--
作者：
Assalauova D;Kim YY;Bobkov S;Khubbutdinov R;Rose M;Alvarez R;Andreasson J;Balaur E;Contreras A;DeMirci H;Gelisio L;Hajdu J;Hunter MS;Kurta RP;Li H;McFadden M;Nazari R;Schwander P;Teslyuk A;Walter P;Xavier PL;Yoon CH;Zaare S;Ilyin VA;Kirian RA;Hogue BG;Aquila A;Vartanyants IA
利用有限数量的数据，在直线加速器相干光源上的单粒子成像实验中确定了噬菌体PR772的三维结构，空间分辨率为6.9 nm。提出了一种改进的单粒子成像(SPI)实验分析方法，利用有限的数据。结果是基于对噬菌体PR772的研究，这是作为SPI倡议的一部分，在直线加速器相干光源的原子、分子和光学科学仪器上进行的。对现有方法进行了修改，以解决实验数据的缺点：无法从一半的探测器获取信息，以及一次命中的一小部分。对常规SPI分析流程进行了升级，在最终的病毒结构确定步骤中采用了基于期望最大化的衍射图分类和模式分解。所提出的加工流水线使我们能够确定噬菌体PR772的三维结构，而不受对称性限制，空间分辨率为6.9 nm。实验过程中的散射强度和相对较少的单次命中次数限制了获得的分辨率。
The 3D structure of bacteriophage PR772 was determined from a single-particle imaging experiment at the Linac Coherent Light Source, using the limited number of data, with a spatial resolution of 6.9 nm. An improved analysis for single-particle imaging (SPI) experiments, using the limited data, is presented here. Results are based on a study of bacteriophage PR772 performed at the Atomic, Molecular and Optical Science instrument at the Linac Coherent Light Source as part of the SPI initiative. Existing methods were modified to cope with the shortcomings of the experimental data: inaccessibility of information from half of the detector and a small fraction of single hits. The general SPI analysis workflow was upgraded with the expectation-maximization based classification of diffraction patterns and mode decomposition on the final virus-structure determination step. The presented processing pipeline allowed us to determine the 3D structure of bacteriophage PR772 without symmetry constraints with a spatial resolution of 6.9 nm. The obtained resolution was limited by the scattering intensity during the experiment and the relatively small number of single hits.