Rocking motion in solid proteins as studied by solid-state NMR techniques

通过固态核磁共振技术研究固体蛋白质中的摇摆运动

• 批准号: 427658902
• 负责人: Dr. Alexey Krushelnitsky
• 金额: --
• 依托单位: Institut für Physik
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2019
• 资助国家: 德国
• 起止时间: 2018-12-31 至 2023-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/427658902?language=en
• 关键词: Rocking; motion; solid; proteins; studied

The aim of the project is a comparative study of a specific type of molecular dynamics in solid protein samples, overall restricted protein motion as a whole, that is rocking motion. This type of protein mobility was discovered only recently and its nature is still not fully clear. The parameters of the rocking motion, that is the amplitude, the correlation time, the width of the correlation time distribution and the activation energy, will be experimentally determined using the 15N and 13C relaxation (T1rho) and exchange (dipolar and CSA CODEX) solid-state NMR techniques that cover microsecond to millisecond ranges of molecular motions. The experiments will be conducted on two proteins, GB1 and thermophilic proteasome, having very different molecular weight. Both proteins will be studied in a form of microcrystals and amorphous powders at different hydration levels. Thermophilic proteasome will also be investigated in a form of sediment in a magic-angle-spinning rotor. Ultimately, we hope to find answers on the following questions: a) How different is the rocking motion between proteins of different size and structural features? b) What is the difference between the rocking motion of the same protein in crystalline and amorphous states and in MAS-sediments? c) How the hydration layer between proteins affects the parameters of the rocking motion? d) How wide is the correlation times distribution of the rocking motion?

该项目的目的是比较研究固体蛋白质样品中的一种特定类型的分子动力学，即整体受限的蛋白质运动，即摇摆运动。这种类型的蛋白质流动性是最近才发现的，其性质仍然不完全清楚。摇摆运动的参数，即振幅，相关时间，相关时间分布的宽度和活化能，将使用15 N和13 C弛豫（T1rho）和交换（偶极和CSA CODEX）固态NMR技术，覆盖微秒至毫秒范围的分子运动实验确定。实验将在两种蛋白质上进行，GB1和嗜热蛋白酶体，具有非常不同的分子量。这两种蛋白质将在不同的水化水平下以微晶和无定形粉末的形式进行研究。嗜热蛋白酶体也将在魔角旋转转子中以沉积物的形式进行研究。最终，我们希望找到以下问题的答案：a）不同大小和结构特征的蛋白质之间的摇摆运动有何不同？B）相同蛋白质在结晶和非结晶状态下的摇摆运动与在MAS沉淀物中的摇摆运动有什么不同？c）蛋白质之间的水化层如何影响摇摆运动的参数？d）摇摆运动的相关时间分布有多宽？