WAXS AS A PROBE FOR THE STUDY OF PROTEIN STRUCTURE, DYNAMICS AND FUNCTION

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。 广角X射线溶液散射(WAXS)在表征蛋白质的结构、动力学和功能方面具有巨大的潜力，而不需要结晶(Fischetti等人，2003)。我们对WAXS的信息含量进行了理论分析，并对其确定蛋白质二级和三级结构的能力进行了量化(Makowski等人，2008a)。使用不同浓度或温度下蛋白质的WAXS，我们证明WAXS包含关于蛋白质系综内结构波动的大量信息(Makowski等人，2008b)。我们进一步表明，可以使用WAXS估计蛋白质正常运动模式的幅度(Park和Makowski，2008)。我们首次测量了溶液中蛋白质的异常信号，并证明了它可用于测量蛋白质(Fischetti等人，2008年)，包括膜蛋白(Makowski等人，2008c)内的原子间距离。它测量微小结构变化的能力使其成为筛选功能结合事件的优秀工具(Rodi等人，2007年)。本请求的目标是继续收集关于若干项目的数据，这些项目将扩大和发展这些最近取得的成功。特别是，我们将开展几个相关项目，利用WAXS研究蛋白质的结构和动力学，包括：(I)详细分析突变对艾滋病毒蛋白酶动态行为的影响；(Ii)估计艾滋病毒蛋白酶催化过程中分子运动的广度；(Iii)分析配体状态和突变对血红蛋白动态行为的影响；(Iv)分析腺苷酸激酶在配体结合和催化活性过程中发生的结构变化。

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. Wide-angle x-ray solution scattering (WAXS) has significant potential for characterizing the structure, dynamics and function of proteins without the need for crystallization (Fischetti et al., 2003). We have carried out a theoretical analysis of the information content of WAXS and quantitated its capabilities for determining the secondary and tertiary structure of a protein (Makowski et al., 2008a). Using WAXS from proteins at different concentrations or temperatures, we demonstrated that WAXS contains substantial information about the structural fluctuations within an ensemble of proteins (Makowski et al., 2008b). We have further shown that the amplitudes of normal modes of motion of a protein can be estimated using WAXS (Park and Makowski, 2008). We have carried out the first measurement of the anomalous signal from proteins in solution, and demonstrated that it can be used to measure interatomic distances within proteins (Fischetti et al., 2008), including membrane proteins (Makowski et al., 2008c). Its power for measurement of small structural changes makes it an excellent tool for screening of functional binding events (Rodi et al., 2007). The goal of the present request is to continue data collection on a number of projects that will expand and develop these recent successes. In particular, we will carry out several related projects that will utilize WAXS for the study of the structure and dynamics of proteins, including: (i) A detailed analysis of the effect of mutations on the dynamic behavior of HIV protease; (ii) Estimation of the breadth of molecular motion during catalysis of HIV protease; (iii) Analysis of the effect of ligand state and mutations on the dynamic behavior of hemoglobin; (iv) analysis of the structural changes that occur during ligand binding and catalytic activity of adenylate kinase.