Triple-axis X-ray diffraction analyses of lysozyme crystals

High-resolution triple-axis X-ray diffraction techniques have been used to monitor the defect structure in hen egg-white lysozyme crystals. Analyses f rom the (440), (<1(2)over bar>0) and (160) reflections showed significant d ifferences in the intensity distribution around the respective reciprocal-l attice points. This work suggests that X-ray diffraction analytical methods developed primarily for relatively perfect inorganic crystals can be succe ssfully applied to structurally defective macromolecular crystals. The anal ysis of defects at high angular resolution is complicated, however, by the observation that protein crystals lie at the convergence of the kinematic ( ideally imperfect) and dynamic (ideally perfect) treatments of diffraction.