Structural Studies of Proteins by Paramagnetic Solid-State NMR Spectroscopy

固态核磁共振（NMR）是一种光谱技术，其使得能够在大型生物分子（超分子）组装体的背景下对蛋白质和核酸进行结构、动力学和相互作用的原子研究。包括淀粉样蛋白（负责神经退行性疾病的分子酶）、脂质膜蛋白复合物和染色质的广泛的此类组装体在基本生物过程和机制中发挥重要作用。在这个项目中，PI正在开发新的固态NMR方法，用于确定蛋白质结构和相互作用，重点是测量长程结构约束，并克服与传统固态NMR技术相关的一些关键挑战。 该项目的研究目标与涉及研究生、本科生和高中生不同群体的教育和外联活动相结合。这些活动包括每年在PI实验室为本科生和当地高中生组织的密集的全日制暑期研究实习计划，旨在通过向学生介绍化学，生物学和物理学界面的前沿跨学科研究，直接影响学生的教育经历的早期阶段，建立他们对自己和科学能力的信心，并鼓励他们以一种广泛的、基于发现的方式来思考科学。最终目标是提高学生在STEM领域的参与度和保留率。正在开发的新型NMR方法的独特之处在于使用共价连接的顺磁标签，通过多维NMR方法，可以同时访问多个蛋白质位点的约20个电子-核距离限制。最近已经证明可以通过使用顺磁固态NMR以从头开始的方式阐明蛋白质结构，目前的项目旨在通过开发紧凑和通用的金属结合标签来进一步推进这种方法，该标签允许测量广泛的顺磁效应，系统地探索顺磁固态NMR高分辨率蛋白质结构测定的限制，并将该技术的应用范围从微晶相的模型球状蛋白扩展到生物大分子的大组装体。

Solid-state nuclear magnetic resonance (NMR) is a spectroscopic technique, which enables atomistic studies of structure, dynamics and interactions to be performed for proteins and nucleic acids in the context of large bio-molecular (supramolecular) assemblies. A wide range of such assemblies, which include amyloids (molecular assembiles responsible for neurodegenerative diseases), lipid membrane protein complexes and chromatin, play important roles in fundamental biological processes and mechanisms. In this project, the PI is developing new solid-state NMR methodologies for the determination of protein structures and interactions, which focus on measurements of long-range structural restraints and overcome some of the key challenges associated with conventional solid-state NMR techniques. The research aims of the project are integrated with education and outreach activities involving diverse groups of graduate, undergraduate and high-school students. These activities, which include intensive, full-time summer research internship programs for undergraduate and local high-school students organized annually in the PI's laboratory, aim to directly impact students in the earliest stages of their educational experience by introducing them to cutting edge interdisciplinary research at the interface of chemistry, biology, and physics, building their confidence in themselves and their scientific abilities, and encouraging them to think of science in a broad, discovery-based manner. The ultimate goal is to increase student participation and retention in the STEM fields.The unique feature of the proposed novel NMR methods being developed lies in their use of covalently-attached paramagnetic tags, which enable up to ~20 Å electron-nucleus distance restraints to be simultaneously accessed for multiple protein sites via multidimensional NMR approaches. Already having recently demonstrated that it is possible to elucidate protein structures in a de novo manner by using paramagnetic solid-state NMR, the current project aims to further advance this methodology by developing compact and versatile metal binding tags that permit measurements of a broad range of paramagnetic effects, systematically exploring the limits of high-resolution protein structure determination by paramagnetic solid-state NMR, and expanding the realm of applicability of this technology beyond model globular proteins in microcrystalline phase to large assemblies of biological macromolecules.