Protein crystallography for progress in life science. X-ray crystal structure analysis and structural biological chemistry

ADP-Ribose pyrophosphatase reaction was traced by cryo-trapping protein crystallography at atomic resolutions around 1 Å. Several intermediate states were identified but dynamic structure changes in a climax of the hydration reaction were blurred by instabilities of the transition state. Crystal structures of photosystem II (PSII) were resolved at resolutions around 1.9 Å. Two structures of the oxygen-evolving complex (OEC) in a PSII homodimer were clearly different in an asymmetric unit under a threshold of radiation dose, 0.12 MGy, although the polypeptide frameworks of PSII, surrounding the OEC, were the same with each other. The reaction mechanism of ADPRase and the OEC structure alteration of PSII were discussed considering atomic parameter errors and reliabilities of their structures. (author)