Pande K, Schwander P, Schmidt M, Saldin D K
Department of Physics, University of Wisconsin-Milwaukee, Milwaukee, WI 53211, USA.
Department of Physics, University of Wisconsin-Milwaukee, Milwaukee, WI 53211, USA
Philos Trans R Soc Lond B Biol Sci. 2014 Jul 17;369(1647):20130332. doi: 10.1098/rstb.2013.0332.
We propose a method for deducing time-resolved structural changes in uncrystallized biomolecules in solution. The method relies on measuring the angular correlations of the intensities, when averaged over a large number of diffraction patterns from randomly oriented biomolecules in solution in a liquid solvent. The experiment is somewhat like a pump-probe version of an experiment on small angle X-ray scattering, except that the data expected by the algorithm are not just the radial variation of the averaged intensities. The differences of these correlation functions as measured from a photoexcited and dark structure enable the direct calculation of the difference electron density with a knowledge of only the dark structure. We exploit a linear relation we derive between the difference in these correlation functions and the difference electron density, applicable for small structural changes.
我们提出了一种推断溶液中未结晶生物分子时间分辨结构变化的方法。该方法依赖于测量强度的角相关性，这是在对液体溶剂中溶液里随机取向的生物分子的大量衍射图样进行平均时得到的。该实验有点类似于小角X射线散射实验的泵浦-探测版本，只是算法预期的数据不仅仅是平均强度的径向变化。通过光激发结构和暗结构测量得到的这些相关函数的差异，仅需了解暗结构就能直接计算差分电子密度。我们利用了我们推导得出的这些相关函数的差异与差分电子密度之间的线性关系，该关系适用于小的结构变化。
