Analytical Ultracentrifuge

描述（由申请人提供）：托马斯杰斐逊大学Kimmel癌症中心的关键数量的研究人员有许多悬而未决的项目，需要一种定量方法来测量生物样品的四级结构及其缔合常数。为此，我们建议购买Beckman Optima XL-I分析超浓缩仪。该仪器非常适合这些项目，并显着扩展了我们的分子相互作用核心设施的能力。利用该仪器，我们将直接研究的具体领域包括：1）动力蛋白和动力肌动蛋白多聚体复合物的热力学特性，动力蛋白活性和货物结合的调控，2）研究参与膜融合的病毒糖蛋白肽段的寡聚化状态和流体动力学特性，3）tRNA-蛋白复合物和遗传信息的解码机制，4）蛋白质与蛋白质之间的相互作用，5）蛋白质与蛋白质之间的相互作用，以及蛋白质与蛋白质之间的相互作用。4）蛋白质-蛋白质相互作用拮抗剂的表征; 5）表征由抑制蛋白（调节G蛋白偶联受体信号传导的蛋白质家族）的活化诱导的构象变化; 6）TCR、pMHC和CD 8的胞外域的平衡结合常数和化学计量的表征。此外，该仪器还将加强两个额外的核心设施（X射线和小分子筛选设施）以及研究生教育（PR 613，结构生物学研究生课程，其结构是学生将教授的每种技术应用于实际样品）。选择的分析超浓缩仪是Beckman Optima XL-I。该仪器允许使用干涉光学器件或UV/可见光光学器件进行检测。干涉模式对折射率敏感，因此不需要分析物具有天然发色团。因此，这将允许测量具有低分子消光系数、小分子拮抗剂和膜结合蛋白的样品。干涉光学器件还提供了快速的数据收集，可用于产生用于沉降速度分析的高质量数据。另一方面，测量大范围（190至800 nM）吸光度的能力允许同时测量多组分系统中的单个组分。

DESCRIPTION (provided by applicant): A critical number of investigators at the Kimmel Cancer Center of Thomas Jefferson University have a number of pending projects that require a quantitative method for measuring the quaternary structure of biological samples and their association constants. To this end, we propose to acquire the Beckman Optima XL-I analytical ultracentrifuge. This instrument is well suited for these projects and significantly extends the capabilities of our molecular interaction core facility. Specific areas that we will immediately address using this instrumentation are: 1) Thermodynamic characterization of multimeric dynein and dynactin complexes in relation to the regulation of dynein activity and cargo binding; 2) To study the oligomerization state and hydrodynamic properties of peptide segments derived from viral glycoproteins involved in membrane fusion; 3) tRNA-protein complexes and the mechanism of decoding genetic information; 4) Characterization of Protein-Protein Interaction Antagonists; 5) Characterize conformational changes induced by activation of arrestins, a family of proteins that regulate G protein-coupled receptor signaling; 6) Characterization of the equilibrium binding constants and the stochiometry of the ectodomains of the TCR, the pMHC and the CD8. In addition, the instrument will enhance two additional core facilities (X-ray and small molecule screening facilities) as well as graduate education (PR613, a graduate course on structural biology, is structured such that students apply each technique taught to an actual sample). The analytical ultracentrifuge of choice is the Beckman Optima XL-I. This instrument permits detection using either interference optics or UV/visible optics. The interference mode is sensitive to the refractive index, and thus, does not require the analyte to have a natural chromaphor. Thus, this will permit measurement of samples with low molecular extinction coefficients, small molecule antagonist and membrane bound proteins. The interference optics also provides rapid data collection useful for producing high quality data for sedmentation velocity analysis. On the other hand, the ability to measure absorbance over a large range (190 to 800 nM) allows simultaneous measurement of individual components in a multicomponent system.