• 主题
高级搜索  >
历史搜索 清空历史
首页> 美国卫生研究院文献>Proceedings of the National Academy of Sciences of the United States of America >Measuring and modeling diffuse scattering in protein X-ray crystallography
【2h】

Measuring and modeling diffuse scattering in protein X-ray crystallography

机译：蛋白质X射线晶体学中散射散射的测量和建模

代理获取
本网站仅为用户提供外文OA文献查询和代理获取服务，本网站没有原文。下单后我们将采用程序或人工为您竭诚获取高质量的原文，但由于OA文献来源多样且变更频繁，仍可能出现获取不到、文献不完整或与标题不符等情况，如果获取不到我们将提供退款服务。请知悉。
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

X-ray diffraction has the potential to provide rich information about the structural dynamics of macromolecules. To realize this potential, both Bragg scattering, which is currently used to derive macromolecular structures, and diffuse scattering, which reports on correlations in charge density variations, must be measured. Until now, measurement of diffuse scattering from protein crystals has been scarce because of the extra effort of collecting diffuse data. Here, we present 3D measurements of diffuse intensity collected from crystals of the enzymes cyclophilin A and trypsin. The measurements were obtained from the same X-ray diffraction images as the Bragg data, using best practices for standard data collection. To model the underlying dynamics in a practical way that could be used during structure refinement, we tested translation–libration–screw (TLS), liquid-like motions (LLM), and coarse-grained normal-modes (NM) models of protein motions. The LLM model provides a global picture of motions and was refined against the diffuse data, whereas the TLS and NM models provide more detailed and distinct descriptions of atom displacements, and only used information from the Bragg data. Whereas different TLS groupings yielded similar Bragg intensities, they yielded different diffuse intensities, none of which agreed well with the data. In contrast, both the LLM and NM models agreed substantially with the diffuse data. These results demonstrate a realistic path to increase the number of diffuse datasets available to the wider biosciences community and indicate that dynamics-inspired NM structural models can simultaneously agree with both Bragg and diffuse scattering.
机译：X射线衍射具有提供有关大分子结构动力学的丰富信息的潜力。为了实现这一潜力，必须测量当前用于推导大分子结构的布拉格散射和报告电荷密度变化相关性的扩散散射。到目前为止，由于需要花费大量精力来收集扩散数据，因此对蛋白质晶体的扩散散射的测量一直很少。在这里，我们提出了从亲环蛋白A和胰蛋白酶的晶体中收集的扩散强度的3D测量。使用最佳数据收集标准，从与布拉格数据相同的X射线衍射图像获得测量值。为了以一种实用的方式对潜在的动力学建模，可以在结构优化期间使用它，我们测试了蛋白质运动的平移-自由-旋转（TLS），类液体运动（LLM）和粗粒度正态（NM）模型。 LLM模型提供了运动的全局图，并针对扩散数据进行了改进，而TLS和NM模型则提供了原子位移的更详细和独特的描述，并且仅使用了布拉格数据中的信息。尽管不同的TLS分组产生相似的布拉格强度，但它们产生了不同的扩散强度，但都与数据不一致。相反，LLM模型和NM模型都与扩散数据基本吻合。这些结果证明了增加可用于更广泛的生物科学界的扩散数据集数量的现实途径，并表明以动力学为灵感的NM结构模型可以同时与布拉格散射和扩散散射相吻合。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
代理获取

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号