New methods development for structure determination of multihelical membrane proteins in their native-like lipid bilayers by solid-state NMR with applications

在这项由化学部化学测量和成像计划资助的项目中，亚历山大·内佐罗夫教授正在利用固体核磁共振(NMR)波谱研究膜蛋白(MPS)在类似天然条件下的变化。膜蛋白具有过多的生物学功能，但其分解结构的数量仍然相对较少。固态核磁共振技术使研究人员能够对在几乎生理条件下难以或不可能结晶的MPS进行结构-功能研究。本研究中发展的核磁共振波谱方法将这项技术的能力扩展到多螺旋膜蛋白。本项目的主要目的是通过开发新的波谱工具来改变定向膜蛋白的固态核磁共振，包括距离测量和密集谱区的分配方法。此外，基于纳米孔和定向大盘的柔性脂质组成的新的膜模拟物正在被创造出来，以监测脂质诱导的MPS的构象变化。探讨了脂质双层的动力学性质，包括膜包埋蛋白质的旋转扩散和双层的粘度。未来的潜在应用包括确定与阿尔茨海默病和其他神经疾病有关的人乙酰胆碱受体的结构。作为这一项目的广泛影响，这项研究的高度跨学科性质为参与其中的年轻科学家提供了多才多艺的培训。作为外展活动，涅佐罗夫博士通过一位凯南研究员的指导，将他的研究成果推广到高中教育和STEM项目。

In this Project funded by the Chemical Measurement and Imaging program of the Chemistry Division, Professor Alexander Nevzorov is studying membrane proteins (MPs) under their native-like conditions by solid-state Nuclear Magnetic Resonance (NMR) spectroscopy. Membrane proteins perform a plethora of biological functions, yet the number of their solved structures remains relatively small. The solid-state NMR technique allows researchers to perform structure-function studies of MPs that are difficult or impossible to crystallize at nearly physiological conditions. NMR spectroscopic methods developed during this research expand capabilities of this technique to multihelical MPs.The main purpose of this project is to transform solid-state NMR of oriented membrane proteins (MPs) by developing new spectroscopic tools including methods for distance measurements and assignment of crowded spectral regions. Moreover, new membrane mimetics of flexible lipid composition based on nanopores and oriented macrodisks are being created to monitor lipid-induced conformational changes of MPs. Dynamic properties of lipid bilayers are probed including rotational diffusion of membrane-embedded proteins and the bilayer viscosity. Potential future applications include structure determination of the human Acetylcholine receptor involved in the Alzheimer's disease and other neurological disorders. As broader impacts of this project, the highly interdisciplinary nature of this research provides versatile training for the young scientists involved. As outreach activities, via mentorship of a Kenan Fellow, Dr. Nevzorov promotes the results of his research to high-school education and STEM programs.