Conformational dynamics in peptides and proteins on the nanoseconds to microseconds time scale

纳秒至微秒时间尺度的肽和蛋白质的构象动力学

• 批准号: 320671684
• 负责人: Professor Dr. Thomas Kiefhaber
• 金额: --
• 依托单位: Abteilung Proteinbiochemie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2016
• 资助国家: 德国
• 起止时间: 2015-12-31 至 2021-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/320671684?language=en
• 关键词: Conformational; dynamics; peptides; proteins; nanoseconds

Proteins exist in an equilibrium between different conformational states. The transitions between these states are closely connected to their biological function. In this project we aim to investigate conformational dynamics in peptides and proteins on the nanoseconds to microseconds time scale. Dynamics on this time scale are experimentally difficult to characterize and are thus only poorly understood. We will use experimental biophysical methods to study conformational equilibria in peptides and proteins in order to determine their structural, thermodynamic and dynamic properties. In the proposed experiments we will couple fast triplet-triplet-energy-transfer (TTET) to conformational equilibria to obtain information on equilibrium fluctuations on the nanoseconds to microseconds time scale. This method is sensitive for local and global unfolding reactions and is able to discriminate between different conformational substates, even when they are structurally very similar. The experiments will yield both thermodynamic and dynamic information on the equilibria. In addition, we will conduct hydrogen/deuterium (H/D) exchange and high-pressure NMR experiments, which will give detailed structural information on the different conformational states. We will study the dynamics of alpha-helical und beta-hairpin peptides as well as different variants of the actin-binding villin headpiece domain (HP35, HP45 and HP67). In parallel, the group of Prof. Lillian Chong will study the same model systems with molecular dynamics (MD) simulations with explicit water. The combination of results from our experimental studies and the all-atom MD simulations will give a detailed structural and dynamic picture of conformational fluctuations in proteins and peptides.

蛋白质存在于不同构象状态之间的平衡状态。这些状态之间的转换与它们的生物功能密切相关。在这个项目中，我们的目标是在纳秒到微秒的时间尺度上研究多肽和蛋白质的构象动力学。这种时间尺度上的动力学在实验上很难描述，因此人们对它的了解很少。我们将使用实验生物物理方法来研究多肽和蛋白质的构象平衡，以确定它们的结构、热力学和动力学性质。在拟议的实验中，我们将把快速三重态-三重态能量转移(TTET)耦合到构象平衡，以获得纳秒到微秒时间尺度上的平衡涨落信息。这种方法对局部和全局展开反应很敏感，能够区分不同的构象亚态，即使它们在结构上非常相似。这些实验将产生有关平衡的热力学和动力学信息。此外，我们还将进行氢/氢(H/D)交换和高压核磁共振实验，这些实验将提供关于不同构象状态的详细结构信息。我们将研究α-螺旋和β-发夹多肽以及肌动蛋白结合绒毛蛋白头盔结构域的不同变体(HP35、HP45和HP67)的动力学。同时，Lillian Chong教授的团队将使用显式水进行分子动力学(MD)模拟来研究相同的模型系统。将我们的实验研究结果和全原子分子动力学模拟相结合，将给出蛋白质和多肽构象波动的详细结构和动态图像。