Protein Structure and Folding at Low Temperature

该建议涉及蛋白质折叠的两个方面， 稳定性：部分折叠物种的性质，特别是 熔融球状态，以及决定一个 特殊的折叠途径。 长期目标是学习 多肽的氨基酸序列如何引导折叠 天然状态，并决定蛋白质的稳定性 构象 相对紧凑的蛋白质构象 状态，通常被称为熔融球状态，已经被 显示为某些重折叠的中间体， 蛋白质，并在一定的变性下保持稳定 一些蛋白质的条件。 其中一个目标是 研究是为了增加对分子的理解， 熔融小球的细节和物理性质。 熔融 小球状态将在平衡和 瞬时重折叠条件。 此外， 折叠将通过使用来自 停流动力学中分子的不同区域 在环境温度和零度以下的温度下进行实验。 一 各种生物物理技术将被用于从结构上 从几个不同的特征熔融球状态 蛋白质（以建立一般性）;这些包括 FTIR、圆二色性（CD）、荧光和流体动力学 半径测量 此外，动力学实验使用 将进行停流荧光和CD。

This proposal concerns two aspects of protein folding and stability: the nature of partially-folded species, especially the molten globule state, and the factors which determine a particular folding pathway. The long-term goals are to learn how the amino acid sequence of a polypeptide guides the folding to the native state, and determines the stability of protein conformations. A relatively compact protein conformational state, often referred to as the molten globule state, has been shown to be an intermediate in the refolding of certain proteins, and to be stable under certain denaturation conditions for some proteins. One of the goals of this research is to increase the understanding about the molecular details and physical properties of molten globules. The molten globule state will be studied under both equilibrium and transient refolding conditions. In addition the pathway of folding will be mapped out by using specific signals from different regions of the molecule in stopped-flow kinetics experiments at both ambient and subzero temperatures. A variety of biophysical techniques will be used to structurally characterize the molten globule state from several different proteins (in order to establish generalities); these include FTIR, circular dichroism (CD), fluorescence and hydrodynamic radius measurements. In addition kinetic experiments using stopped-flow fluorescence and CD will be performed.