HIGH-RESOLUTION MACROMOLECULAR STRUCTURE DETERMINATION USING CCD DETECTORS AND SYNCHROTRON-RADIATION

Background: Synchrotron. radiation sources have made impressive contri butions to macromolecular crystallography. The delay in development of appropriate X-ray detectors has, however, been a significant limitati on to their efficient use. New technologies, based on charge-coupled d evices (CCDs), provide capabilities for faster, more accurate, automat ed data collection. Results: A CCD-based X-ray detector has been devel oped for use in macromolecular crystallography and has been in operati on for about one and a half years at the Cornell High Energy Synchrotr on Source. It has been used for a variety of crystallographic projects , including a number of high-resolution structural studies. The statis tical quality of the data, the detector's ease and efficiency of use, and the growing number of structural results illustrate the practical utility of this new detector system. Conclusions: The new detector has enhanced capabilities for measuring diffraction patterns from crystal s of macromolecules, especially at high resolution, when the X-ray int ensities are weak. The survey of results described here ranges from vi rus crystallography to weakly diffracting small-molecule structure det ermination and demonstrates the potential of CCD detectors when combin ed with synchrotron radiation sources.