STRATEGY CALCULATION FOR PHASING PROTEIN CRYSTAL STRUCTURES IN THE PRESENCE OF R

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 尽管有证据表明选择用于数据收集的能量对数据的全球质量没有太大影响[Shimizu，Hirata，Hasegawa，Ueno&Yamamoto(2007)J.同步辐射。14 4-10]，不同能量下的局部辐射损伤效应还没有得到充分的研究。实验研究了9 keV和14.5 keV的二硫键对溶菌酶的还原速率。二硫键的损伤发生相对较快，易于观察和量化，辐射损伤机理与其他元素相同。初步结果表明，二硫键的减少速度与地点有关，暴露的位置越多，衰减速度就越快，在选择用于研究的两个能量下，衰减速度没有明显差异。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Although there is evidence that the energy chosen for data collection does not have a great deal of effect in the global quality of the data [Shimizu, Hirata, Hasegawa, Ueno & Yamamoto (2007) J. Synchrotron Radiat. 14 4-10], the effects of local radiation damage at different energies have not been sufficiently studied. Experiments have been undertaken to study the reduction rate of disulfide bridges at 9 and 14.5 keV on lysozyme. The damage to disulfide bridges happens relatively quickly and it is easy to observe and quantify, and the radiation damage mechanism is thought to be the same as for other elements. Preliminary results indicate that the rate of reduction of the disulfide bridges is site depending, with more exposed sites showing an increased rate of decay and there is no apparent difference in the rate of decay at the two energies chosen for the study.