Molecular Basis of Substrate Translocation in the Drug/H+ Antiporter 1 Family

药物/H 逆向转运蛋白 1 家族底物易位的分子基础

• 批准号: 10414517
• 负责人: Min Lu
• 金额: $ 32.76万
• 依托单位: ROSALIND FRANKLIN UNIV OF MEDICINE & SCI
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-06-15 至 2026-04-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10414517
• 关键词: Alcoholism; Amino Acids; Antimicrobial Resistance; Binding; Biochemical; Biological; Bipolar Disorder; Brain; Cations; Cell membrane; Cells; Chemical Structure; Clinical; Communicable Diseases; Complex; Coupled; Couples; Data; Development; Drug Binding Site; Drug Efflux; Drug Modelings; Escherichia coli; Family; Gilles de la Tourette syndrome; Goals; Human; Huntington Disease; Infection; Integral Membrane Protein; Lead; Ligands; Light; Major Depressive Disorder; Malignant Neoplasms; Mediating; Membrane; Membrane Proteins; Mental Depression; Modeling; Molecular; Movement; Multi-Drug Resistance; Mutagenesis; Mutate; Neuromodulator; Neurotoxins; Neurotransmitters; Parkinson Disease; Pathogenicity; Patients; Pharmaceutical Preparations; Physiological; Polyamines; Process; Protein Export Pathway; Proteins; Publishing; Reporting; Research; Roentgen Rays; Schizophrenia; Site; Structure; Therapeutic; Transmembrane Transport; Treatment Efficacy; Variant; Work; alcoholism therapy; antimicrobial; antiport; antiporter; autism spectrum disorder; base; clinically relevant; deprotonation; effective therapy; experience; inhibitor; insight; membrane model; microorganism; monoamine; multi drug transporter; mutant; nervous system disorder; neuropsychiatry; neurotransmission; novel strategies; novel therapeutic intervention; overexpression; pathogenic bacteria; protonation; solute; structural biology; targeted treatment; therapeutic target; unpublished works; vesicle transport

Molecular Basis of Substrate Translocation in the Drug/H+ Antiporter 1 Family Summary Integral membrane proteins known as multidrug transporters extrude therapeutic drugs of diverse chemical structures across cell membranes, impeding the treatment of human cancers, infectious diseases, and neurological disorders. Currently we lack a deep and mechanistic understanding of how these proteins export drugs or how they can be thwarted. We will study the structure and mechanism of a model multidrug transporter, MdfA from Escherichia coli, which couples the influx of H+ to the efflux of various antimicrobials and belongs to the ubiquitous Drug/H+ Antiporter 1 (DHA1) family. MdfA orthologues are present in many pathogenic microorganisms, and the overexpression of E. coli MdfA can lead to antimicrobial resistance in clinical patients. Thus, MdfA represents an important target for therapeutic exploitation to overcome multidrug resistance. Furthermore, the SLC18 antiporters, which are the human counterparts of MdfA in the DHA1 family, conduct the H+-dependent vesicular transport of monoamine neurotransmitters, polyamine neuromodulators, and neurotoxins. The human SLC18 antiporters are essential for brain function and promising therapeutic targets for battling alcoholism, autism spectrum disorders, bipolar disorder, Huntington disease, major depressive disorder, Parkinson’s disease, schizophrenia, and Tourette syndrome. Our long-term objective is to understand how the DHA1 multidrug transporters and human SLC18 antiporters translocate their substrates and how their function can be modulated for potential therapeutic benefit. Notably, prior biochemical studies have suggested that MdfA translocates certain substrates via a non-canonical mechanism. Drawing upon these data and our experience in membrane protein structural biology, we will accomplish two aims: (1) to elucidate the molecular basis for simultaneous translocation of two mono-cationic substrates by a DHA1; (2) to reveal the structural mechanism for non-canonical, DHA1- mediated extrusion of di-cationic therapeutics. By combining crystallographic and biochemical studies, we will acquire new insights into how a DHA1 translocates two substrates concurrently, how a DHA1 inhibitor differs from the substrate, and how a DHA1 exports a therapeutic drug in two consecutive and yet different deprotonation/protonation cycles. The new conceptual framework and DHA1 structures obtained from this study will serve as a stepping-stone toward devising novel strategies to evade or inhibit the clinically relevant multidrug transporters, which may rescue therapeutic efficacy against multidrug-resistant cells and halt the spread of untreatable infections. Furthermore, our work will offer a springboard for the mechanistic studies of human SLC18 antiporters, which will shed new light on how they utilize the electrochemical H+ gradient to translocate monoamine neurotransmitters, neurotoxins, or polyamine neuromodulators, across vesicular membranes.

药物/H+抗胞菌1家族中底物易位的分子基础 概括 积分膜蛋白被称为多药转运蛋白挤出潜水员的治疗药物 跨细胞膜的化学结构，阻碍了人类癌症的治疗 疾病和神经系统疾病。目前，我们对如何有深刻而机械的理解 这些蛋白质出口药物或如何挫败它们。我们将研究结构和机制 大肠杆菌的模型多果转运蛋白MDFA的MDFA，该转运蛋白伴随着H+的影响 各种抗菌药物的外排，属于无处不在的药物/H+抗毒剂1（DHA1）家族。 MDFA直系同源物存在于许多致病性微生物中，大肠杆菌的过表达 MDFA可以导致临床患者的抗菌素耐药性。那是MDFA代表一个重要的 热剥削以克服多药电阻的目标。此外，SLC18 DHA1家族中MDFA的人类对应者的抗植物进行H+依赖性 单胺神经递质，多胺神经调节剂和神经毒素的水泡转运。 人类SLC18抗植物对于大脑功能和有希望的治疗靶标至关重要 与酒精中毒，自闭症谱系障碍，躁郁症，亨廷顿疾病，主要抑郁症作斗争 疾病，帕金森氏病，精神分裂症和图雷特综合征。我们的长期目标是 了解DHA1多药转运蛋白和人类SLC18抗植物如何转移他们的 底物及其功能如何调节潜在的治疗益处。值得注意的是，先验 生化研究表明，MDFA通过非典型的易位某些底物 机制。利用这些数据以及我们在膜蛋白结构生物学方面的经验，我们 将实现两个目标：（1）阐明分子基础，以简单转运两个 DHA1的单照式底物； （2）揭示了非典型的DHA1-的结构机制 介导的大苯甲酸疗法的扩展。通过结合晶体学和生化研究， 我们将获得有关DHA1如何同时易位两个基质的新见解，即DHA1如何 抑制剂与底物不同，DHA1如何连续两次出口治疗药物 然而不同的去质子化/质子化周期。新的概念框架和DHA1结构 从这项研究获得的将成为制定新型逃避策略或 抑制临床相关的多药转运蛋白，这可能会挽救热效率 多药耐药细胞并停止了无法治疗的感染的传播。此外，我们的工作将提供 用于人类SLC18抗植物的机械研究的跳板，这将为新的启示 他们如何利用电化学H+梯度来转移单胺神经递质， 神经毒素或多胺神经调节剂，跨水泡膜。