Development of X-ray Data Processing System for Protein Microcrystals

Abstract

The bottleneck in protein structure determination by X-ray crystallography is to obtain protein crystals with suitable size and sufficient diffracting power, and sometimes only microcrystals can be obtained. For such microcrystals, the use of X-ray microbeams is essential to collect diffraction data at high S/N ratio. However, radiation damage hampers complete and high-resolution data collection from a single microcrystal, and therefore multiple crystals are required. At microbeam beamline BL32XU, SPring-8, the workflow for protein microcrystals is established and automated. One of the key programs is SHIKA, which suggests microcrystal positions by finding diffraction spots from low-dose raster scan. Automatically collected datasets are processed and merged by KAMO, a new open-source data processing pipeline for automating the whole data processing tasks in the case of multiple datasets. These developments greatly facilitated the structure analyses from microcrystals.