Detailed assessment of X-ray induced structural perturbation in a crystalline state protein.Takeda, K., Kusumoto, K., Hirano, Y., Miki, K.
(2010) J.Struct.Biol. 169: 135-144
- PubMed: 19782139
- DOI: 10.1016/j.jsb.2009.09.012
- Primary Citation of Related Structures:  3A39
- PubMed Abstract:
The positions of hydrogen atoms significantly define protein functions. However, such information from protein crystals is easily disturbed by X-rays. The damage can not be prevented completely even in the data collection at cryogenic temperatures. T ...
The positions of hydrogen atoms significantly define protein functions. However, such information from protein crystals is easily disturbed by X-rays. The damage can not be prevented completely even in the data collection at cryogenic temperatures. Therefore, the influence of X-rays should be precisely estimated in order to derive meaningful information from the crystallographic results. Diffraction data from a single crystal of the high-potential iron-sulfur protein (HiPIP) from Thermochromatium tepidum were collected at an undulator beamline of a third generation synchrotron facility, and were merged into three data sets according to X-ray dose. A series of structures analyzed at 0.70A shows detailed views of the X-ray induced perturbation, such as the positional changes of hydrogen atoms of a water molecule. Based on the results, we successfully collected a low perturbation data set using attenuated X-rays. There was no influence on the crystallographic statistics, such as the relative B factors, during the course of data collection. The electron densities for hydrogen atoms were more clear despite the slightly lower resolution.
Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan.