LABELING HEPATITIS B CORE PARTICLES

本子项目是利用由NIH/NCRR资助的中心赠款提供的资源的众多研究子项目之一。子项目和研究者（PI）可能已经从另一个NIH来源获得了主要资金，因此可以在其他CRISP条目中表示。列出的机构是中心的，不一定是研究者的机构。了解蛋白质和多蛋白质组合的三维结构对于理解基本的生物过程和设计更有效的药物非常重要。对于许多这样的物质，它们不能结晶，而且对于核磁共振分析来说太大了，电子显微镜（EM）是唯一可以提供有用的结构信息的技术。电子密集分子的附着，包含重金属元素簇，可以高效地散射电子，这对于EM数据的收集和分析通常是必要的。高分辨率EM的从业者通常只能从商业供应商那里获得两种电子密度材料和一套有限的附着方法。在许多情况下，这些资源失败了，必须放弃目标或费力地重新设计目标。我们建议创造新的电子密集化合物，并开发方法来快速确定将它们连接到目标蛋白质的最佳方式。目标是为EM社区提供一套扩展的蛋白质标记材料和技术，以便可以对更大比例的靶标进行结构表征。这项工作将包括等量化学合成、化学分析以测量附着反应的总体效率，以及在多功能病毒颗粒平台上进行严格的电磁测试。然后，成功的方法将应用于迄今为止无法通过电子显微镜进行结构表征的重要蛋白质系统。

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. Knowledge of the three-dimensional structures of proteins and multi-protein assemblies is of great importance to the understanding of fundamental biological processes and the design of more effective Pharmaceuticals. For many such species, which cannot be crystallized and are too large for NMR analysis, electron microscopy (EM) is the only technique that can provide useful structural information. The attachment of electron-dense molecules, containing clusters of heavy metallic elements that scatter electrons with high efficiency, is often necessary to EM data collection and analysis. Practitioners of high-resolution EM usually have access to only two electron-dense materials and a limited set of attachment methods available from commercial suppliers. In many cases, these resources fail and the target must be either abandoned or laboriously re-engineered. We propose to create new electron-dense compounds and develop methods to rapidly identify the best ways to connect them to target proteins. The goal is to give the EM community an expanded set of materials and techniques for protein labeling, so that a greater fraction of targets can be structurally characterized. The effort will be comprised of equal parts chemical synthesis, chemical analysis to measure the overall efficiency of attachment reactions, and rigorous EM testing on a versatile virus particle platform. Successful methods will then be applied to important protein systems that have thus far resisted structural characterization by electron microscopy.