IN-SITU UV/VIS SPECTROSCOPY FOR MACROMOLECULAR CRYSTALLOGRAPHY

用于大分子晶体学的原位紫外/可见光谱

• 批准号: 7598177
• 负责人: S M SOLTIS
• 金额: $ 0.99万
• 依托单位: STANFORD UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-03-01 至 2008-02-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7598177
• 关键词: Computer Retrieval of Information on Scientific Projects Database; Crystallography; Data; Data Set; Electronics; Funding; Future; Goals; Grant; In Situ; Institution; Measurement; Microscope; Monitor; Optics; Oxidation-Reduction; Porphyrins; Positioning Attribute; Proteins; Reaction; Research; Research Personnel; Resources; Source; Spectrum Analysis; Structure; United States National Institutes of Health; absorption; base; design; instrument; oxidation; photolysis; research study

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. The goal of this project is to enable the simultaneous acquisition of x-ray diffraction data and single crystal absorption spectra in the UV/Visible and infrared regions. Analysis of the absorption spectrum in the UV (190 - 400 nm) and visible (400 - 800 nm) regions provides information about the electronic state of proteins while in the crystalline state. During diffraction experiments, spectroscopic measurements were analyzed to confirm the redox state. Future experiments will include detecting the presence of reaction intermediates or to potentially monitor degradation products that may be produced either by photolysis or by x-rays. A single crystal microspectrophotometer was set up on BL11-1 to record spectra from crystals on the goniometer. Positioning of the optics and a 2nd microscope were refined for ease of use. Data were collected from crystals containing an Fe porphyrin that showed degradation of the oxidation state after 5 degrees of x-ray data. A complete data set was collected from 12 crystals each providing approximately 5 degrees of data. The resulting structure¿s oxidation state could be unambiguously characterized. Based on these experiments, the instrument design is now being optimized further.

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。 该项目的目标是能够同时获得紫外/可见光和红外区的X射线衍射数据和单晶吸收光谱。对紫外(190-400 nm)和可见光(400-800 nm)区域的吸收光谱的分析提供了有关蛋白质在结晶态时的电子状态的信息。在衍射实验中，对光谱测量进行了分析，以确认氧化还原状态。未来的实验将包括检测反应中间体的存在，或潜在地监测可能由光解或X射线产生的降解产物。在BL11-1上安装了单晶显微分光光度计，用于记录测角仪上晶体的光谱。光学元件的定位和第二个显微镜都经过了改进，便于使用。数据是从含有铁卟啉的晶体中收集的，该晶体在5度X射线数据后显示氧化态的退化。从12个晶体中收集了完整的数据集，每个晶体提供大约5度的数据。由此产生的S氧化态的结构可以明确地描述出来。在这些实验的基础上，仪器的设计正在进一步优化。