Pulsed Q-band EPR Spectrometer

描述（由申请人提供）：申请资金用于在范德比尔特大学完成布鲁克EleXsys 580 q波段FT-EPR系统的购买。该设备将被五个不同的已建立的研究小组和他们的一些合作者使用，以对广泛的氮氧化物自旋标记蛋白质进行DEER测量，这些蛋白质已经使用定点自旋标记进行了研究。仪器和方法的最新进展使时域EPR成为表征自旋标记蛋白质结构和动力学的重要补充。在构成本应用程序核心用户组的十个NIH资助项目中，所要求的设备将用于：1)增加我们通过DEER测量蛋白质“长”（bbb20 - 25e）探针间距离的能力；2)增加小样本（包括重组膜蛋白）的信噪比；3)允许对DEER数据进行多频分析；4)为评价自旋标签之间的相对取向提供取向选择性；5)提供可靠的w- q波段测量能力。在五个申请实验室中，所要求的仪器将通过提供独特的新测量能力来全面表征广泛的可溶性和膜结合蛋白的结构和动力学，从而产生直接和实质性的影响，这些蛋白具有明确的生物医学重要性。所要求的仪器也将提供给范德比尔特大学和周边地区的其他研究人员，因为他们正在开发涉及自旋标签的新项目。内部监督委员会将确保设备的公平利用，日常操作将由经验丰富的EPR光谱专家处理。

DESCRIPTION (provided by applicant): Funds are requested to complete the purchase of a Bruker EleXsys 580 Q-band FT-EPR system at Vanderbilt University. This equipment will be utilized by five different established research groups and a number of their collaborators to make DEER measurements on a wide range of nitroxide spin-labeled proteins that are already being studied using site-directed spin-labeling. Recent advances in instrumentation and methodology have positioned time-domain EPR as an essential complement to cw-EPR for characterizing the structures and dynamics of spin-labeled proteins. In the ten NIH funded projects that constitute the core user group of this application, the requested equipment will be utilized to: 1) increase our capacity for measuring "long" (> 20 - 25 E) inter-probe distances in proteins by DEER; 2) increase signal to noise for small samples including reconstituted membrane proteins; 3) permit multifrequency analysis of DEER data; 4) provide orientation selectivity for assessment of relative orientations between spin labels; and 5) provide the capability to make reliable cw-Q-band measurements. In each of the five applicant laboratories, the requested instrumentation will have an immediate and substantial impact by providing unique new measurement capabilities for full characterization of the structures and dynamics of wide range of soluble and membrane bound proteins that are of clear biomedical importance. The requested instrumentation will also be made available to other investigators at Vanderbilt and in the surrounding area as they develop new projects that involve spin-labeling. Equitable utilization of the equipment will be assured by an internal oversight committee and day-to-day operation will be handled by an experienced EPR spectroscopist.