Is inhibiting pili electrical conductivity a new anti-virulence strategy?

抑制菌毛导电性是一种新的抗毒策略吗？

• 批准号: 10387218
• 负责人: Matthew J. Guberman-pfeffer
• 金额: $ 6.76万
• 依托单位: YALE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-01-01 至 2022-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10387218
• 关键词: Adhesions; Adhesiveness; Adhesives; Antibiotic Resistance; Bacteria; Bacterial Adhesion; Bacterial Pili; Binding Sites; Biochemistry; Biophysics; Cells; Charge; Chemistry; Collaborations; Communities; Dangerousness; Development; Development Plans; Docking; Educational workshop; Electric Conductivity; Electron Transport; Electrons; Fellowship; Filament; Free Energy; Infection; Institutes; Intestines; Journals; Ligands; Mechanics; Mediating; Mentors; Mentorship; Microbial Biofilms; Molecular; Molecular Conformation; Mutation; Nature; Outcome; Pathogenicity; Pilum; Play; Point Mutation; Population; Process; Property; Pseudomonas aeruginosa; Publishing; Pulmonary Cystic Fibrosis; Research; Resistance; Role; Science; Structure; Surface; Techniques; Tensile Strength; Theoretical model; Therapeutic; Thinness; Training; Universities; Virulence; Work; adhesion process; antagonist; antimicrobial; career development; chronic infection; cystic fibrosis patients; design; drug discovery; electrical property; extracellular; graduate student; high throughput screening; host-microbe interactions; human pathogen; insight; interfacial; kinetic model; microbial; microbial community; microbiota; molecular dynamics; nanowire; novel therapeutics; pathogen; pathogenic bacteria; pressure; prevent; professor; prospective; quantum; rational design; receptor; small molecule; success; symposium; theories; treatment strategy

Project Summary Adhesion of bacteria to host cells is an essential step in the initiation of an infection, and yet, the mechanisms that make bacteria sticky are not fully understood. A long list of human pathogens, including Pseudomonas aeruginosa in the lungs of cystic fibrosis patients, become anchored to host cells using thin (<10 nm), long (>1 µm), and mechanically strong (capable of withstanding pN to nN forces) filaments called pili. The pili latch onto surfaces through receptor-ligand interactions, and only very recently discovered, extracellular electron transfer. Bacteria with more electrically conductive pili tend to be more adhesive. By elucidating the mechanistic basis for this observation, we seek to establish design rules for manipulating microbe-host interactions for therapeutic purposes. New therapies that inhibit pili-mediated charge transfer could be realized to block the formation of biofilms by pathogenic species, or to correct imbalances in the populations of adhered intestinal tract microbiota. To realize these possibilities, we specifically aim to establish the relative contributions of mechanical and electrical mechanisms in bacterial adhesion mediated by pili. Alchemical and steered molecular dynamics simulations will be used to assess the change in stability and tensile strength of pili as a function of point mutations associated with differently adherent bacteria. A quantum mechanical/molecular mechanical implementation of Marcus theory, combined with a kinetic model, will be used to compute the electrical conductivity of different pili. The pili will feature mutations according to a direct electronic modulation strategy: Standard residues will be replaced with substituent-bearing unnatural counterparts that have similar steric but different electronic properties. The obtained structure-function insights will drive the second aim of our research to rationally design and evaluate pili antagonists. Fragment dissolved molecular dynamics will be used to identify prospective binding sites, into which ligands will be docked in a high throughput screen and optimized by free energy perturbation techniques. The work will be undertaken at Yale University under the mentorship of Professor Nikhil S. Malvankar of the Microbial Science Institute within the Molecular Biophysics and Biochemistry department, and in collaboration with John Randolph Huffman Professor Victor S. Batista of the Chemistry department. Their combined expertise with bacterial nanowires (Dr. Malvankar) and the theoretical modeling of interfacial electron transfer processes (Dr. Batista) will serve as unique assists for the success of the project. The fellowship training plan involves publishing in high impact journals and presenting at conferences for the biomedical and chemistry communities. It also includes the opportunity to mentor graduate students. The career development plan includes attending professional development workshops organized by the Office of Postdoctoral Affairs, as well as courses relevant to the project.

项目摘要 细菌与宿主细胞的粘附是感染起始的重要步骤，然而， 使细菌具有粘性的机制尚未完全了解。一长串人类病原体，包括 铜绿假单胞菌在囊性纤维化患者的肺部，成为锚定宿主细胞使用薄（<10 纳米）、长（>1微米）和机械强度（能够承受pN到nN力）的称为皮利的细丝。 皮利通过受体-配体相互作用附着在表面上，直到最近才发现， 细胞外电子传递具有更多导电性皮利的细菌往往更具有粘性。通过 为了阐明这种观察的机械学基础，我们试图建立操纵的设计规则， 微生物与宿主的相互作用。抑制纤毛介导的电荷转移的新疗法 可以实现阻止病原物种形成生物膜，或纠正生物膜中的不平衡。 粘附的肠道微生物群的群体。 为了实现这些可能性，我们的具体目标是建立机械的相对贡献， 以及皮利介导的细菌粘附的电机制。炼金术和操纵分子动力学 模拟将用于评估作为点的函数的皮利的稳定性和抗拉强度的变化 与不同粘附细菌相关的突变。量子力学/分子力学 马库斯理论的实施，结合动力学模型，将用于计算电 不同皮利的电导率。根据直接电子调制，皮利将以突变为特征 策略：标准残基将被具有类似结构的带有取代基的非天然对应物取代。 但电子性质不同。获得的结构-功能见解将推动第二个目标， 本研究旨在合理设计和评价皮利拮抗剂。碎片溶解分子动力学将是 用于鉴定预期的结合位点，在高通量筛选中配体将对接到该结合位点中， 通过自由能微扰技术优化。 这项工作将在耶鲁大学进行，由Nikhil S.马尔万卡尔 微生物科学研究所的分子生物物理学和生物化学系， 与约翰兰多夫霍夫曼教授维克托S.化学系的巴蒂斯塔。他们的 结合细菌纳米线的专业知识（Malvankar博士）和界面的理论建模 电子转移过程（巴蒂斯塔博士）将作为该项目的成功独特的援助。的 研究金培训计划包括在高影响力期刊上发表文章，并在 生物医学和化学社区。它还包括指导研究生的机会。的 职业发展计划包括参加由办公室组织的专业发展讲习班， 博士后事务，以及与项目相关的课程。