Mechanisms of Allostery and Molecular Recognition in the Small Multidrug Resistance Family

多药耐药小家族的变构和分子识别机制

• 批准号: 10451577
• 负责人: Nathaniel J. Traaseth
• 金额: $ 45.36万
• 依托单位: NEW YORK UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-07-15 至 2024-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10451577
• 关键词: Acids; Active Biological Transport; Antibiotic Resistance; Antibiotics; Bacteria; Bacterial Drug Resistance; Binding; Biochemical; Biological; Biological Assay; Charge; Chemical Structure; Chemistry; Clinic; Collaborations; Computing Methodologies; Data; Defense Mechanisms; Development; Drug Modelings; Drug Transport; Drug resistance; Effectiveness; Family; Foundations; Goals; Grant; Knowledge; Knowledge Discovery; Mediating; Membrane Proteins; Methods; Modeling; Molecular; Molecular Conformation; Multi-Drug Resistance; Mutagenesis; Nature; Organism; Outcomes Research; Pathogenicity; Pharmaceutical Preparations; Phase; Phenotype; Plant alkaloid; Play; Poison; Positioning Attribute; Property; Proteins; Protons; Pump; Repression; Research; Role; Shapes; Side; Source; Specificity; Structure; Substrate Specificity; System; Testing; Transport Process; Work; base; biophysical analysis; biophysical techniques; comparative; computational platform; deprotonation; design; drug discovery; efflux pump; guanidinium; inhibitor; insight; molecular recognition; multi drug transporter; multiple drug use; mutant; novel; pH gradient; pathogenic bacteria; response; theories; tool

Project Summary Bacterial drug resistance is a worldwide problem that limits the effectiveness of antibiotics in the clinic. While there are several molecular mechanisms that contribute to drug resistant phenotypes, it is well established that efflux pumps play a prominent role in pathogenic bacteria. Indeed, multidrug transporters constitute a fundamental mechanism used by bacteria to survive in the presence of toxic compounds by binding and transporting a broad array of structurally diverse compounds. The long-term goals of this project are to discover novel mechanisms used by multidrug transporters and to harness this knowledge to predict and control function. In this competitive renewal, we are now poised to tackle the major challenge in the field of understanding how efflux pumps achieve broad drug specificity required for conferring multidrug resistance. To accomplish this goal, we need to establish a comprehensive understanding of the catalytic cycle for an efflux pump system amenable to detailed biological, biochemical and biophysical studies. For this reason, our proposal will use EmrE from the SMR family as the model drug transporter since it embodies the minimal level of complexity while retaining the key features shared among all secondary active efflux pumps. Aim 1 will test an occluded-state theory that we hypothesize is widely used by efflux pumps for drug binding. Aim 2 will seek to define the molecular basis for substrate-induced activation of dynamics versus inhibitor-induced repression of dynamics, as well as development of a computational platform for predicting binding and transport. Finally, Aim 3 will set out to determine the molecular basis of binding specificity versus promiscuity through a comparative analysis of two subfamilies within the SMR family that have markedly different specificity profiles. Each of these Aims works synergistically toward our long-term goal of articulating novel transport mechanisms and applying our knowledge to develop models for making predictions about function. A major strength of this project is the integrated nature of the approach which utilizes significant collaboration and a combination of biological, biophysical, and computational methods aimed at unveiling general transport mechanisms designed by nature and shared among other multidrug efflux pumps. The outcomes of this research will make a significant impact in understanding efflux-mediated multidrug resistance, and the approaches and methods developed will be translatable to knowledge discovery in other efflux systems.

项目摘要 细菌耐药性是一个世界性的问题，限制了抗生素在临床上的有效性。而 有几种分子机制导致耐药表型，已经确定， 外排泵在病原菌中起着重要作用。事实上，多药转运蛋白构成了 细菌在有毒化合物存在下生存的基本机制， 运输大量结构不同的化合物。这个项目的长期目标是发现 多药转运蛋白使用的新机制，并利用这些知识来预测和控制功能。 在这一竞争性的更新中，我们现在准备好应对理解如何实现这一领域的主要挑战。 外排泵实现了赋予多药耐药性所需的广泛的药物特异性。为了实现这一目标， 我们需要建立一个全面的了解催化循环的外排泵系统的责任 详细的生物学、生物化学和生物物理学研究。因此，我们的建议将使用来自 SMR家族作为模型药物转运蛋白，因为它体现了最低水平的复杂性，同时保留了 所有二级主动外排泵共有的关键特征。目标1将测试一个封闭状态理论，我们 假设被外排泵广泛用于药物结合。目标2将寻求定义以下的分子基础： 底物诱导的动力学激活与底物诱导的动力学抑制，以及 开发用于预测结合和运输的计算平台。最后，目标3将着手 通过比较分析两种结合特异性与滥交的分子基础， SMR家族中的亚家族具有显著不同的特异性谱。每一个目标都有效 协同实现我们的长期目标，阐明新的运输机制和应用我们的知识 来开发预测功能的模型。该项目的一个主要优势是综合性 的方法，利用重要的合作和生物，生物物理， 计算方法，旨在揭示一般运输机制设计的性质和共享之间 其他多药外排泵。这项研究的结果将对理解 外排介导的多药耐药，开发的方法和途径将可转化为 知识发现在其他外排系统。