Accelerated AChE Reactivator Design by Mechanistic Neutron Scattering Studies

描述（由申请人提供）：我们在此提出了一项尖端生物物理学研究，旨在确定神经毒剂肟再活化中结构上强加的限制因素， 有机磷农药（OP）抑制人乙酰胆碱酯酶（hAChE）。我们将专注于表征hAChE蛋白质结构域的运动在溶液中的关键促进再活化以及精确的质子结构中的hAChE活性中心参与的亲核取代共价共轭磷。这项研究将使用尖端技术来表征再活化相关的分子运动的hAChE在溶液中的基础上的X射线和中子散射的平衡和解决的时间从ps到分钟的间隔。高分辨率接头 在室温下对hAChE晶体的X射线/中子衍射将用于解析hAChE活性中心中质子和完整水分子的精确位置。散射和衍射的研究将依赖于比较分析的本地，OP共轭，和老化的乙酰胆碱酯酶单独，并在复杂的选择结构上不同的肟再活化剂，并将旨在确定肟的结构特征，最佳的克服限制所施加的结构动力学和质子分布在乙酰胆碱酯酶活性中心。所获得的信息加上先进的计算分析和模拟将用于设计原型加速肟活化剂的OP-hAChE。原型加速再活化剂的结构将可用于合成和改进，使用我们与位于拉霍亚的斯克里普斯研究所的研究人员合作开发的现有药物设计管道。

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.