Structural chemistry of inhibitor binding to Aldose Reductase: An integrated approach combining subatomic resolution crystallography, microcalorimetry, multipolar modeling and quantum modeling

该项目涉及位于斯特拉斯堡IGBMC、马尔堡大学、南希大学和哥廷根大学的四个实验室。该项目的总体目的是研究抑制剂与醛糖还原酶(AR)的结合，AR是一种与糖尿病并发症有关的蛋白质，并开发最先进的方法学来完成这一任务。它从AR-抑制剂复合体的亚原子分辨结晶学研究(Strasburg)和AR-抑制剂结合的微量热学研究(Marburg)的实验数据，到由抑制剂结合的量子模型发布的结合能计算(Nancy和Strasburg)。该项目需要最先进的精细化技术，由Goettingen小组提供用于球形原子的各向异性精细化，由Nancy小组提供用于多极建模。这些小组已经开始了AR-IDD594抑制剂复合体的合作，其中的数据已经收集到0.66ä的分辨率(这种大小的蛋白质的最高记录)。AR-IDD594复合体已经在活性部位和特异性口袋中显示出抑制剂结合模式。计划继续对另外三种缓蚀剂：393、509和860进行这项工作，这些缓蚀剂可以产生能够进行原子分辨衍射的复杂晶体。这些抑制剂的数据将被测量，结构将被改进，多极和量子计算将被完成。抑制剂和结合抑制剂的蛋白质残基的电荷状态将从这些改进中确定。能量微扰计算将提供不同缓蚀剂之间结合能差异的信息，这将与微量热数据相关联。最终结果将是对抑制剂结合能的详细了解，这对药物设计研究非常有用，并在结晶学和建模方法方面取得了进展。

This project involves four laboratories, situated at the IGBMC, Strasbourg; the University of Marburg; the University of Nancy and the University of Goettingen. The overall purpose of the project is to study the binding of inhibitors to Aldose Reductase (AR), a protein involved in diabetic complications, and to develop state of the art methodology in order to fulfill this task. It goes from the experimental data from subatomic resolution crystallographic studies of AR-inhibitor complexes (Strasbourg) and microcalorimetric studies of AR-inhibitor binding (Marburg) to binding energy calculations issued from the quantum modeling of inhibitor binding (Nancy and Strasbourg). The project needs state of the art refinement technology, to be provided by the Goettingen group for anisotropic refinement of spherical atoms and by the Nancy group for multipolar modeling. These groups have already started a collaboration on the complex of AR-IDD594 inhibitor, of which data has been collected to a resolution of 0.66 Å ( the highest ever recorded for a protein of this size). The AR-IDD594 complex has already shown the inhibitor binding mode in the active site and the specificity pocket. It is planned to continue this work on three other inhibitors: 393, 509 and 860, which produce complex crystals capable of atomic resolution diffraction. The data of these inhibitors will be measured, the structures will be refined, and multipolar and quantum calculations will be done. Charge states of the inhibitor and of the protein residues binding the inhibitor will be determined from these refinements. Energy perturbation calculations will provide information about the difference in binding energies between the different inhibitors, which will be correlated with the microcalorimetric data. The end result will be a detailed understanding of the inhibitor binding energies, very useful for drug design studies, and advances in the crystallographic and modeling methods.