SRLS APPROACH FOR STUDIES ON ORIENTED MEMBRANE PROTEINS BY SOLID-STATE NMR

通过固态核磁共振研究定向膜蛋白的 SRLS 方法

• 批准号: 8364106
• 负责人: Alexander A. Nevzorov
• 金额: $ 0.16万
• 依托单位: CORNELL UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-09-01 至 2012-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8364106
• 关键词: Accounting; Address; Data; Diffusion; Evolution; Funding; Grant; Length; Magnetism; Membrane; Membrane Proteins; Methods; Modeling; Motion; NMR Spectroscopy; National Center for Research Resources; Phase; Physiologic pulse; Principal Investigator; Protein Dynamics; Proteins; Relaxation; Research; Research Infrastructure; Resources; Source; Technology; Time; United States National Institutes of Health; Vertebral column; cost; research study; solid state nuclear magnetic resonance

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. In solid-state NMR of oriented membrane proteins, the traditional method of NMR spin relaxation analysis, which assumes predominantly fast isotropic motions, does not extract adequately and fully the information inherent to the experimental data. Here, the primary issue is how to address the great complexity of protein dynamics, including the global and restricted local motions. In general, in oriented membrane proteins one should expect highly constrained local motions of the loop domains and the backbone superimposed onto the overall uniaxial rotational diffusion of the protein (e.g. of the type observed in magnetically aligned bicelles. The unique SRLS approach developed by Freed and co-workers accounts most generally for the relationship between the global and local motions, for the local ordering, and for the relevant magnetic interactions. The implementation of the model for the 2D-ELDOR experiment is directly generalizable to solid-state NMR pulse sequences, which include switching on the transverse B1 field with defined pulse phases and lengths for prolonged periods of time during the evolution. Moreover, the features of the SRLS model allow one to include torsional motions of the protein within the membrane's restoring potential, as well as the effects of collective fluctuations of the membrane on the protein dynamics. We will adapt the SRLS model to solid-state NMR spectroscopy of oriented membrane proteins with the purpose of extracting the dynamic and structural information from the analyses of spectral lineshapes and cross-polarization build-up rates.

这个子项目是利用资源的许多研究子项目之一。 由NIH/NCRR资助的中心拨款提供。对子项目的主要支持 子项目的首席调查员可能是由其他来源提供的， 包括美国国立卫生研究院的其他来源。为子项目列出的总成本可能 表示该子项目使用的中心基础设施的估计数量， 不是由NCRR赠款提供给次级项目或次级项目工作人员的直接资金。 在定向膜蛋白的固体核磁共振中，传统的以快速各向同性运动为主的核磁共振自旋松弛分析方法不能充分和完全地提取实验数据所固有的信息。在这里，首要的问题是如何解决蛋白质动力学的巨大复杂性，包括全局运动和受限的局部运动。一般来说，在定向的膜蛋白中，人们应该期待环域和骨架的高度受限的局部运动叠加到蛋白质的整体单轴旋转扩散上(例如，在磁性排列的双分子中观察到的类型)。由Freed和同事开发的独特的SRLS方法最一般地考虑了全局和局部运动之间的关系，局部有序，以及相关的磁相互作用。2D-Eldor实验模型的实现可直接推广到固态核磁共振脉冲序列，其中包括在演化过程中打开具有定义的脉冲相位和长度的横向B1场以延长时间段。此外，SRLS模型的特点使人们能够考虑膜恢复势内蛋白质的扭转运动，以及膜的集体波动对蛋白质动力学的影响。我们将把SRLS模型应用于定向膜蛋白的固体核磁共振波谱，目的是从谱线形状和交叉极化建立速率的分析中提取动态和结构信息。