Liu Haiguang, Poon Billy K, Janssen Augustus J E M, Zwart Peter H
Physical Biosciences Division, Lawrence Berkeley National Laboratories, One Cyclotron Road, Berkeley, CA 94720, USA.
Acta Crystallogr A. 2012 Sep;68(Pt 5):561-7. doi: 10.1107/S0108767312029637. Epub 2012 Aug 15.
Ultrashort X-ray pulses from free-electron laser X-ray sources make it feasible to conduct small- and wide-angle scattering experiments on biomolecular samples in solution at sub-picosecond timescales. During these so-called fluctuation scattering experiments, the absence of rotational averaging, typically induced by Brownian motion in classic solution-scattering experiments, increases the information content of the data. In order to perform shape reconstruction or structure refinement from such data, it is essential to compute the theoretical profiles from three-dimensional models. Based on the three-dimensional Zernike polynomial expansion models, a fast method to compute the theoretical fluctuation scattering profiles has been derived. The theoretical profiles have been validated against simulated results obtained from 300 000 scattering patterns for several representative biomolecular species.
来自自由电子激光X射线源的超短X射线脉冲，使得在亚皮秒时间尺度上对溶液中的生物分子样品进行小角和广角散射实验成为可能。在这些所谓的涨落散射实验中，经典溶液散射实验中通常由布朗运动引起的旋转平均的缺失，增加了数据的信息含量。为了从这些数据中进行形状重建或结构精修，从三维模型计算理论轮廓至关重要。基于三维泽尼克多项式展开模型，已经推导出一种计算理论涨落散射轮廓的快速方法。针对几种代表性生物分子物种的300 000个散射图案的模拟结果，对理论轮廓进行了验证。
