• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文学位 >Design, synthesis, and quantitative structural activity relationships of carboxylate ligands for the HisB10 binding site of hexameric insulin and the use of dynamic nuclear magnetic resonance (DNMR) spectroscopy to probe the phenolic ligand binding mechanism.
【24h】

Design, synthesis, and quantitative structural activity relationships of carboxylate ligands for the HisB10 binding site of hexameric insulin and the use of dynamic nuclear magnetic resonance (DNMR) spectroscopy to probe the phenolic ligand binding mechanism.

机译：六聚体胰岛素HisB10结合位点的羧酸盐配体的设计，合成和定量结构活性关系，以及使用动态核磁共振（DNMR）光谱法检测酚类配体的结合机理。

获取原文
获取原文并翻译 | 示例
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

The insulin hexamer is an allosteric protein that displays positive and negative cooperativity and half-site reactivity that is controlled at two different binding sites by homotropic and heterotropic binding interactions. These binding sites consist of two anion sites situated along the three-fold axis of symmetry in R3 units of T3R3 and R6 and phenolic ligand sites located at the dimer-dimer interface of all allosteric forms of the protein. In this thesis we show that carboxylate ligands can be designed computationally using molecular mechanics and dynamics techniques that bind with affinities greater than carboxylates previously reported. We also report the Quantitative Structure Activity Relationship (QSAR) between both computationally and experimentally derived descriptors and the experimentally determined binding affinity of various carboxylates. These analyses show that in addition to the molecular volume of the ligand, the polarizability of the electrons of the molecule and the basic nature of the carboxylate coordinating the Lewis acid Zn(II) control the affinity of the carboxylate for the HisB10 site. Finally, the binding mechanism of phenolic ligands was investigated through the use of 19F Dynamic NMR studies with the phenolic ligand alpha,alpha,alpha-Trifluoro-m-cresol. Ligand association and dissociation is not obvious when viewing X-ray crystal structures of R6 hexameric insulin phenolic ligand complexes. Amino acid residues cover the ligand when bound to the phenolic ligand binding site making discovery of a mechanism for dissociation structurally difficult. We determined in the liquid phase that the rate of exchange between ligand free in solution and ligand bound to protein is fast to moderately fast on the NMR timescale. At -15°C, the exchange slowed enough to allow deconvolution of the free and bound peaks whereby equilibrium constants, populations, and T2 relaxations were determined. These parameters were then used along with the program DNMR5 to fit theoretical lineshapes onto experimental lineshapes at varying concentrations of alpha,alpha,alpha-Trifluoro-m-cresol to determine binding off rates. These data along with previously reported dynamic and structural work were used to develop possible mechanistic schemes by with phenolic ligands can bind to the phenolic ligand binding sites on R-state hexameric insulin.
机译：胰岛素六聚体是一种变构蛋白，显示正和负的协同作用以及半位反应性，该半位反应性由同向和异向结合相互作用控制在两个不同的结合位点。这些结合位点由在T3R3和R6的R3单元中沿对称三轴对称的两个阴离子位点和位于蛋白质所有变构形式的二聚体-二聚体界面处的酚配体位点组成。在本论文中，我们表明可以使用分子力学和动力学技术通过计算来设计羧酸盐配体，该技术结合的亲和力大于先前报道的羧酸盐。我们还报告了定量的结构活性关系（QSAR）之间的计算和实验得出的描述符和各种羧酸盐的实验确定的结合亲和力。这些分析表明，除了配体的分子体积之外，分子电子的极化性和配位路易斯酸Zn（II）的羧酸盐的基本性质还控制了羧酸盐对HisB10位点的亲和力。最后，通过对酚类配体α，α，α-三氟-间甲酚的19F动态NMR研究，研究了酚类配体的结合机理。当查看R6六聚体胰岛素酚类配体复合物的X射线晶体结构时，配体缔合和解离并不明显。当氨基酸残基结合到酚类配体结合位点时，氨基酸残基覆盖了配体，这使得结构解离的机理难以发现。我们在液相中确定，在NMR时标上，溶液中游离的配体和与蛋白质结合的配体之间的交换速率快到中等快。在-15°C，交换速度足够慢，以允许自由峰和结合峰解卷积，从而确定平衡常数，总体和T2弛豫。然后将这些参数与DNMR5程序一起使用，以在各种浓度的α，α，α-三氟-间甲酚中将理论线形拟合到实验线形上，以确定结合率。这些数据以及先前报道的动力学和结构研究被用于开发可能的机理方案，其中酚类配体可以与R型六聚体胰岛素上的酚类配体结合位点结合。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号