Exploiting Water Network Perturbations in Protein Binding Sites

项目摘要/摘要 水使生命成为可能。以至于寻找地外生命就是寻找液态水。然而， 大体上，陆地药物的发现仍然忽视了水分子。原因在于它的复杂性和复杂性。 它对生物分子相互作用的贡献多才多艺，尽管它看起来很简单。我之前的研究已经 研究了水在配基识别和选择性中的作用，以及它在改进配基发现方面的作用。 最近，我的实验室建立了水网络的流动性和配体结合的亲和力之间的联系 到蛋白质。更广泛地说，这项工作突出了供水网络在应对 蛋白质和配体的变化。我的长期目标是将原子尺度的水的摆动与蛋白质的变化联系起来 构象景观和最终的生物体健康。为了实现这一目标，我渴望为实现 更动态的蛋白质功能视图，整合了目前被忽视的蛋白质灵活性和 水合作用。这一点很重要，因为低温结构占蛋白质数据库的95%， 提供一个扭曲的静态图像，然后用它来设计配体。拟议工作的目标是 制定一个定义和利用水网络动态的务实框架。因为水无处不在 在所有生物界面上都可以发现这个概念，它超越了蛋白质与配体的相互作用，扩展到许多领域， 包括蛋白质-蛋白质相互作用、变构、蛋白质进化和抗性。 我的中心假设是，我们可以利用水分子对环境变化的敏感度 我们的人情。水波动报告动态特征变化的假设将在 通过1)温度、2)突变和3)配体的扰动而产生的三个特异区。1)重新定义水 蛋白质结构中的网络：我假设生理温度提供了一个较少扭曲的观点 蛋白质晶体中的水网络比使用普通低温冷冻获得的结构更好。我们将测试 这一假说是通过解决蛋白质在一定温度范围内的晶体结构来实现的。通过暴露冰冻 人工制品，我们可以揭示水网络动态的隐藏变化，这些变化可以有效地用于预测 有约束力的亲和力。2)探索水网络中不同形态的差异：我假设通过使用水 作为变化的报告者，我们可以区分出近乎相同的Hsp90亚型。我们将测试 通过跟踪共同进化的水网络如何在依赖于上下文的情况下响应扰动来实现假说 举止。这将揭示Hsp90领域一直难以利用的异构体的细微差异 几十年来探索疾病中的差异异构体生物学。3)考虑配位体水网络动力学 发现：我假设，包括实验性水网络术语将改善计算对接。 基于我们之前成功地包含了通过计算得出的溶剂化能，我们预计这将 导致新的Hsp90配体将水的扰动降至最低，这是在其他情况下无法发现的。

PROJECT SUMMARY/ABSTRACT Water enables life. So much so that the search for extraterrestrial life is a search for liquid water. However, terrestrial drug discovery still, by and large, ignores water molecules. The reason lies in the complexity and versatility of its contributions to biomolecular interactions, despite its apparent simplicity. My prior research has investigated the role of water in ligand recognition and selectivity, and its utility to improve ligand discovery. Recently, my lab has established a link between the mobility of water networks and the affinity of ligand binding to proteins. More generally, the work highlights the exploitable sensitivity of water networks in response to changes in protein and ligand. My long-term goal is to link atomic-scale water wiggles to changes in the protein conformational landscape and ultimately to organismal fitness. To achieve this, I aspire to pave the path to a more dynamic view of protein function that integrates currently neglected aspects of protein flexibility and hydration. This is important because cryogenic structures, which make up 95% of the Protein Data Bank, deliver a contorted, static image which is then used to design ligands. The objective of the proposed work is to formulate a pragmatic framework that defines and utilizes water network dynamics. As water is ubiquitously found at all biological interfaces, the concept extends beyond protein-ligand interactions to many fields, including protein-protein interactions, allostery, protein evolution and resistance. My central hypothesis is that we can use the exquisite sensitivity of water molecules to contextual changes in our favor. The hypothesis that water fluctuations report on changes in dynamic features will be exploited in three specific areas via perturbation with 1) temperature, 2) mutation and 3) ligands. 1) Re-defining water networks in protein structures: I hypothesize that physiological temperatures provide a less distorted view of water networks within protein crystals than structures obtained using common cryogenic freezing. We will test the hypothesis by solving crystal structures of proteins over a range of temperatures. By exposing freezing artifacts, we can reveal hidden changes in water network dynamics that can be used productively to predict binding affinities. 2) Exploring isoform-specific differences in water networks: I hypothesize that by using water perturbations as a reporter for change, we can distinguish near-identical Hsp90 isoforms. We will test the hypothesis by tracking how co-evolved water networks respond to perturbations in a context-dependent manner. This will expose subtle differences in isoforms that the Hsp90 field has struggled to exploit for decades to explore differential isoform biology in disease. 3) Considering water network dynamics in ligand discovery: I hypothesize that including experimental water network terms will improve computational docking. Based on our previous success of including computationally derived solvation energies, we expect that this will lead to novel Hsp90 ligands that minimize water perturbation, which cannot be discovered otherwise.