AUTOMATIC CENTERING OF PROTEIN CRYSTALS USING X-RAYS

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 为了完全自动化晶体筛选过程，开发并改进了将蛋白质晶体与X射线束自动对准的方法。特别是，已经探索了使用在X射线束中不同晶体位置拍摄的低剂量衍射图像的平均I/Sig(I)的方法。使用图像分析程序DISTL对这些图像进行分析，以估计I/Sig(I)，并在此分析的基础上，在特定的算法中检查和改进了一系列参数，以实现最佳晶体排列，确定并使用晶体的最大衍射力而不是光学中心。通常情况下，晶体可以在2-4分钟内对准。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. In order to fully automate the crystal screening process, methods to automatically align protein crystals to the x-ray beam were developed and refined. In particular, approaches using average I/Sig(I) from low-dose diffraction images taken at various crystal positions in the x-ray beam have been explored. These images were analyzed using the image analysis program, DISTL, in order to estimate I/Sig(I), and based on this analysis, a range of parameters were examined and refined in specific algorithms for optimal crystal alignment, determining and using the maximum diffracting power of the crystal rather than the optical center. Typically crystals can be aligned in 2-4 minutes.