Accelerated AChE Reactivator Design by Mechanistic Neutron Scattering Studies

描述(由申请人提供)：我们建议进行一项尖端的生物物理研究，旨在确定神经毒剂和神经毒剂再激活的结构限制因素。 农药有机磷(OP)对人乙酰胆碱酯酶(HAChE)有抑制作用。我们将重点研究HAChE蛋白结构域在溶液中的运动，以及HAChE活性中心的精确质子结构，这些结构与共价结合磷的亲核取代有关。这项研究将使用尖端技术来表征溶液中HAChE的重新激活相关的分子运动，基于平衡的X射线和中子散射，并在PS到MIN间隔的时间内进行解析。高分辨率关节 室温X射线/中子衍射将被用来确定质子和完全水分子在HACH活性中心的精确位置。散射和衍射研究将依赖于对天然的、OP共轭的和陈化的HAChE的比较分析，以及与选定的结构不同的肟类复活剂的复合体，目的是识别最适合于克服结构动力学和HAChE活性中心中的质子分布施加的限制的肟类的结构特征。所获得的信息与先进的计算分析和模拟相结合，将被用于设计OP-HACH的原型加速肟复活器。原型加速复活剂的结构将利用我们与拉霍亚斯克里普斯研究所的研究人员合作开发的现有药物设计流水线进行合成和改进。

DESCRIPTION (provided by applicant): We propose here a cutting edge biophysical study aimed at identifying structurally imposed limiting factors in oxime reactivation of nerve agent and pesticide organophosphate (OP) inhibited human acetylcholinesterase (hAChE). We will focus on characterizing hAChE protein domain motions in solution critical for facilitating reactivation a well as on precise proton structure in the hAChE active center involved in the nucleophilic substitution of covalently conjugated phosphorus. The study will use cutting edge techniques to characterize reactivation related molecular motions of hAChE in solution based on X-ray and neutron scatter in equilibrium and resolved in time from ps to min intervals. High resolution joint X-ray/neutron diffraction on hAChE crystals at room temperature will be used to resolve precise positions of protons and complete water molecules in the hAChE active center. Both scattering and diffraction studies will rely on comparative analysis of native, OP-conjugated, and aged hAChE alone, and in complex with selected structurally diverse oxime reactivators and will be aimed at identifying structural features of oximes optimal for overcoming limitations imposed by structural dynamics and proton distribution in the hAChE active center. The acquired information coupled with advanced computational analysis and simulation will be used to design prototypic accelerated oxime reactivator of OP-hAChE. The structures of prototypic accelerated reactivators will be made available for synthesis and refinement using our existing drug design pipeline developed in collaboration with researchers of The Scripps Research Institute in La Jolla.