Evaluating the Bilayer-Couple Model of Outer Membrane Vesicle Biogenesis Using Novel Asymmetric Membrane Templates

使用新型不对称膜模板评估外膜囊泡生物发生的双层耦合模型

基本信息

批准号：
9016995
负责人：
Jeffrey Schertzer
金额：
$ 21.93万
依托单位：
STATE UNIVERSITY OF NY,BINGHAMTON
依托单位国家：
美国
项目类别：
财政年份：
2016
资助国家：
美国
起止时间：
2016-01-01 至 2017-12-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9016995
关键词：
Address Antibiotic Resistance Architecture Area Bacteria Bacterial Antibiotic Resistance Biochemical Biogenesis Biological Biophysical Process Caliber Cell Communication Cells Characteristics Communication Complement Computer Simulation Development Disease Drug Delivery Systems Equilibrium Fluorescence Microscopy Foundations Goals Gram-Negative Bacteria Health Horizontal Gene Transfer Immune Immune system In Vitro Lipids Liposomes Mediating Membrane Membrane Biology Membrane Lipids Microbial Biofilms Microfluidics Modeling Molecular Monitor Mono-S Organism Pathogenesis Phospholipids Physiological Play Population Process Pseudomonas Pseudomonas aeruginosa Quinolones Research Role Signal Transduction Sorting - Cell Movement Structure System Techniques Technology Testing Time Toxin Vesicle Virulence Factors antimicrobial biophysical model computerized tools flexibility human disease insight intercalation killings microbial molecular dynamics novel novel strategies particle physical property preference public health relevance research study response simulation small molecule synthetic construct trafficking vaccine development

项目摘要

DESCRIPTION (provided by applicant) Bacterial secretion has long been recognized as an essential facet of microbial pathogenesis and human disease. One important but poorly understood system, which is ubiquitous among Gram-negative organisms, involves packaging cargo into small outer membrane derived vesicles (OMVs). Numerous virulence factors have been found to be transported in this way, and delivery by OMVs often results in increased potency. OMVs have also been implicated in the killing of host cells and competing bacteria, avoidance of and interference with the immune system, horizontal gene transfer mediating antibiotic resistance, biofilm formation, and trafficking small molecule communication signals. Remarkably, little is known about how these versatile structures are formed or how their cargo is selected and packaged. To address this, our team proposed the Bilayer-Couple Model where intercalation of self-produced small molecules into the outer membrane drives the induction of membrane curvature to initiate OMV formation. This is a biochemical/biophysical model that followed the discovery by our team and colleagues that the Pseudomonas Quinolone Signal (PQS) is packaged within and drives biogenesis of OMVs in Pseudomonas aeruginosa. In developing this model, we encountered a problem that is common in membrane biology: while all biological membranes contain asymmetric lipid distributions (leaflet vs. leaflet), it was impossible to generate a useful quantiy of in vitro liposomes matching these characteristics. Thus, weakly-relevant surrogates had to be used. Recently, our team has developed a novel approach for constructing synthetic asymmetric vesicles possessing a bilayer architecture that is more physiologically accurate than any other available system. Our approach utilizes microfluidic technology to build vesicles with controlled size, membrane asymmetry, uniformity, and luminal content. These vesicles are the ideal system to experimentally test the predictions of the Bilayer-Couple Model. To gain a greater physical insight in complement to experiments, we also propose to create the first-ever atomistic molecular dynamics and mesoscopic dissipative particle dynamics simulation of the bacterial outer membrane to discover the specific interactions between PQS and physiological-relevant asymmetric membranes. In particular, this model will help elucidate the detailed dynamics of PQS insertion into the outer membrane, its orientation PQS vs. surrounding lipids in the leaflet and whether its own physical properties direct its observed packaging into OMVs. Using leading edge experimental and computational tools, this proposal will address fundamental aspects of OMV formation, including (1) how PQS interacts with and alters the structure of the outer membrane, (2) whether these interactions are sufficient to initiate OMV formation, and (3) whether PQS itself may contribute to its accumulation in OMVs as cargo. The fundamental mechanistic foundations established through this study will have implications in many aspects of health research, potentially enabling applied topics such as vaccine development and drug delivery, for which OMVs are rapidly becoming exciting candidates.

描述（由申请人提供）细菌的分泌长期以来一直是微生物发病机理和人类疾病。增加效力，避免了免疫系统，水平基因转移介导，生物膜形成和运输小分子通信信号。 WhereLelf生产的L分子进入外模型，以使omv形成降低了我们的发现，即在铜绿中遇到了一个问题。在膜生物学中：所有生物膜的脂质脱脂型（传单与传单）不可能产生有用的体外脂质体匹配这些特征。更多的是，以膜不对称，均匀性和腔内含量来构建这些vesict。动力学模拟与Q的动力学相关的不对称膜。 OMV。使用前沿实验和计算工具，该建议将解决OMV组的基本方面，包括（1）PQS与外膜的结构和变化，（2）相互作用是否是足够的OMV形成和（ 3）PQ本身是否可以在OMV中积累TOT作为货物的基础，这项研究将对健康Rearch的许多方面具有影响令人兴奋的candidididididididididididididididididididididididits。