Protein crystallography microdiffraction

Protein microdiffraction using monochromatic beams is becoming a routine tool at third-generation synchrotron radiation sources. Beam sizes have reached the scale of about 5 mu m, with illuminated crystal volumes of approximately 500 mu m(3), as shown for the case of bovine rhodopsin, which was refined to a resolution of 2.6 angstrom. Progress in X-ray optical systems and instrumentation will enable the method to be extended to smaller beams and smaller crystal volumes.