NONRANDOM UNFOLDED STATES AND PROTEIN STABILITY

描述：本研究计划的目的是寻求更大的 了解存在于其中的非随机结构的重要性 蛋白质的未折叠状态用于蛋白质稳定性和折叠。 FK506 结合蛋白（FKBP）提供了一个独特的系统来识别此类 相关性。 FKBP 在晶体和晶体中的高分辨率结构 解形式可用，并且 FKBP 的平衡展开有 使用各种光谱和方法进行了彻底的表征 生化方法。 另外，对FKBP进行了详细的结构研究 在浓尿素和盐酸胍中展开 进行，证明存在相关的非随机结构 具有特定的残留物。 非随机结构的位置 未折叠的 FKBP 与在 折叠形式，并且与倾向相关性更强 根据统计和预测预测的螺旋和转角构象 二级结构预测的热力学尺度。 另一方面 另一方面，这些初步研究的一个特别令人惊讶的发现是 折叠和展开时形成不同的二级结构 C 末端残基的状态。 诱变和光谱 将结合多种方法来进一步表征展开的形式 FKBP 并详细探讨这些关系。 先前折叠和展开的结构和热力学研究 FKBP将用于理解非随机结构在 展开状态影响FKBP的折叠和稳定性。 角色 非随机结构改变 FKBP 的本机状态稳定性将 确定其他蛋白质中类似结构的一般规则。 在 此外，破译负责的热力学驱动力 折叠时 C 端残基的构象转换将 对蛋白质设计和三维结构有影响 预测。

DESCRIPTION: The objective of this research program is to seek a greater understanding of the significance of non-random structure present in the unfolded states of proteins for protein stability and folding. The FK506 binding protein (FKBP) provides a unique system to identify such correlations. High resolution structures of FKBP in both the crystal and solution forms are available and the equilibrium unfolding of FKBP has been thoroughly characterized using a variety of spectroscopic and biochemical methods. In addition, a detailed structural study of FKBP unfolded in concentrated urea and guanidine hydrochloride has been performed, demonstrating the presence of non-random structure associated with specific residues. The location of the non-random structure in unfolded FKBP was correlated with similar structures observed in the folded form, and was more strongly correlated with the propensity for helical and turn conformations predicted from statistical and thermodynamic scales of secondary structure prediction. On the other hand, a particularly surprising finding from these initial studies was that different secondary structures are formed in the folded and unfolded states for the C-terminal residues. Mutagenesis and spectroscopic approaches will be combined to further characterize the unfolded form of FKBP and to explore these relationships in detail. The previous structural and thermodynamic studies of folded and unfolded FKBP will be used to understand the role that non-random structure in the unfolded state plays in the folding and stability of FKBP. The role of non-random structures in altering native state stability in FKBP will identify general rules for similar structures in other proteins. In addition, deciphering the thermodynamic driving forces responsible for the conformational switch in the C-terminal residue upon folding will have implications in protein design and in three dimensional structure prediction.