Ultrafast time resolved protein X-ray crystallography

我们现在有了所有的工具和方法，使我们能够在真实的时间和超快的时间分辨率下观察蛋白质的功能，探索生物激活的基本过程。随着飞秒X射线自由电子激光源的可用性，它现在在硬X射线制度下以飞秒脉冲持续时间运行，出现了独特的机会，以获得对蛋白质超快结构过程的新的基本见解。在这里，我提出了一个研究计划，飞秒时间分辨X射线晶体学的光诱导反应在光敏蛋白质晶体和支持光谱研究。这些实验的必要的初步工作提供的形式收集的数据在斯坦福大学直线加速器相干光源（LCLS），从超快光学光谱研究的非线性跃迁和脉冲整形控制飞秒人口转移在家庭实验室进行，并从支持建模的晶体学数据质量的基础上测得的源参数。除了主要目标，这是一个飞秒实验与光活性黄色蛋白质晶体，新的实验正在开发首先使用皮秒同步加速器源，增加到现有的选择飞秒泵浦探测研究，并侧重于光开关荧光蛋白。

We now have all the tools and the methodology that allows us to watch proteins function with structural resolution in real time with ultrafast time resolution, probing fundamental processes in biological activation. With the availability of femtosecond X-ray Free Electron Laser sources which now operate in the hard X-ray regime with femtosecond pulse duration, unique opportunities arise to gain fundamental new insight into ultrafast structural processes in proteins. Here, I propose a research programme on femtosecond time-resolved X-ray crystallography of light induced reactions in light sensitive protein crystals and supporting spectroscopic studies. The necessary preliminary work for such experiments are provided in the form of data collected at the Stanford Linac Coherent Light Source (LCLS), from ultrafast optical spectroscopy investigations of non-linear transitions and pulse shaping to control femtosecond population transfer performed in the home laboratory, and from supporting modeling of crystallographic data quality based on measured source parameters. In addition to the primary target, which is a femtosecond experiment with Photoactive Yellow Protein crystals, novel experiments are being developed firstly using picosecond synchrotron sources, to add to the existing choices for femtosecond pump-probe studies and focuses on photoswitchable fluorescent proteins.