EPR Spectrometer Upgrade for Structural Biophysics Core Laboratory

9970177摘要明尼苏达大学的四个主要用户和五个次要用户正在购买EPR仪器升级，以研究肌肉收缩、膜钙转运、光合作用、脂质结合和转运以及蛋白质折叠中涉及的蛋白质的动力学、结构和功能。研究人员正在通过诱变，蛋白质设计，生理学和酶动力学以及各种结构技术研究生物功能和机制，使用最近建立的结构生物物理学核心实验室（SBCL）的共享设施。 新仪器具有以下功能：（1）允许对小而珍贵的样品进行实验，例如突变蛋白质，单肌肉纤维和单蛋白质晶体，以及用于时间分辨EPR实验的可编程数据采集能力，（2）包括用于小定向样品和时间分辨光化学EPR实验的专用谐振器，以及（3）具有第二个更高的光谱仪频率，以增加灵敏度和分辨率并减少数据分析的模糊性。 EPR技术将与肌肉力学同步检测肌肉结构蛋白的结构和动力学，并与衰老过程相关联。瞬态和多频EPR将被用来探测光系统II，光合水氧化复合物的催化位点的周转动力学。脂质结合蛋白和结合脂质之间的动态相互作用将通过溶液和单个蛋白质晶体中的EPR来探测，并与X射线晶体学相协调。

9970177SummaryFour major and five minor users at the University of Minnesota are acquiring an EPRinstrumentation upgrade to study the dynamics, structure, and function of proteins involved in muscle contraction, membrane calcium transport, photosynthesis, lipid binding and transport, and protein folding. The investigators are studying biological function and mechanism through mutagenesis, protein design, physiology, and enzyme kinetics, as well as a variety of structural techniques, using the shared facilities of a recently established Structural Biophysics Core Laboratory (SBCL). The new instrument has capabilities that will (1) allow experiments on small and precious samples, such as mutant proteins, single muscle fibers, and single protein crystals, and the capability for programmable data-acquisition for time-resolved EPR experiments, (2) include specialized resonators for small oriented samples and for time-resolved photochemical EPR experiments, and (3) has a second higher spectrometer frequency, to increase sensitivity and resolution and decrease ambiguity of data analysis. The structure and dynamics of muscle structural proteins will be detected by EPR simultaneously with muscle mechanics and correlated with the aging process. Transient and multi-frequency EPR will be used to probe the kinetics of turnover of the catalytic site of photosystem II, the photosynthetic water-oxidizing complex. The dynamic interaction between lipid binding proteins and bound lipids will be probed by EPR in solution and single protein crystals and coordinated with x-ray crystallography.