Molecular Forces in Microbial Biofilms

这个NSERC发现补助金提案旨在发现稳定各种表面上微生物生物膜形成的分子力的潜在机制。微生物生物膜在加拿大的几个部门（例如食品安全、农业、工业和石油管道、船舶船体涂层等）的大多数主要污垢问题中发挥核心作用，估计每年要花费数十亿美元。这种日益增长的生物膜相关问题背后的一个关键原因是我们对细菌粘附在各种表面上的机制的了解有限，以及缺乏对稳定这些生物膜的分子理解。由于细菌在表面上的初始粘附和小菌落形成是成熟生物膜的关键先决条件，因此本研究计划将针对生物膜形成的初始阶段，并将重点关注在生物膜发展的这些关键阶段赋予生物膜稳定性的“分子力”。特别是，它的目的是解剖细菌的表面粘附分子和底层基板的属性之间的纳米级相互作用，最初解决基板刚度对E的生长的影响。虽然长期以来已经确定底物硬度影响哺乳动物细胞信号传导和干细胞分化，但其对微生物生物膜生长的影响是最近的发现，并且尚未被很好地理解。为了填补基底刚度如何影响稳定生物膜的分子力的差距，我的实验室将开创扫描探针显微镜，光学显微镜和力谱之间的三向相关测量，具有单分子和单细胞分辨率。这种生物膜研究的定量和相关方法不仅可以提供生物膜复杂结构的高分辨率图像，在生理条件下，它还可以量化稳定这些结构的纳米级力。长期目标是扩大研究范围，以涵盖其他基质特性和其他生物膜形成细菌。这将提供一个更普遍的机械见解如何影响的物理化学特性的基板的分子力，赋予生物膜的稳定性。从这项研究计划的结果不仅将进一步我们的机械理解的生物膜的结构稳定性，在坚持不同的表面，它也将导致切实的利益，加拿大工业相关的农业，能源，环境和公共卫生，以及全球人口，特别是随着耐药性微生物的威胁日益增加。此外，由于研究的跨学科性质，它将成为下一代加拿大科学家的优秀培训基地，并将使加拿大处于定量生物膜研究的最前沿。

This NSERC discovery grant proposal seeks to discover mechanisms underlying the molecular forces that stabilize microbial biofilm formation on a wide variety of surfaces. Microbial biofilms play a central role in most major fouling problems in several sectors in Canada (e.g. food safety, agriculture, industrial and oil pipelines, ship hull coatings etc.), and is estimated to cost billions of dollars annually. A key reason behind this growing biofilm-related problems is our limited understanding of the mechanisms by which bacteria adhere to a wide range of surfaces, and the lack of molecular understanding behind the forces responsible for stabilizing these biofilms. As initial adhesion and microcolony formation of bacteria on surfaces are crucial pre-requisites for mature biofilms, this research program will target the initial stages of biofilm formation, and will focus on the “molecular forces” that confer biofilm stability during these critical phases of biofilm development. In particular, it aims to dissect the nanoscopic interplay between bacteria's surface adhesion molecules and the properties of the underlying substrate, initially addressing the influence of substrate stiffness on the growth of E. coli biofilms.While substrate stiffness has long been established to influence mammalian cell signalling and stem cell differentiation, its influence on microbial biofilm growth is rather a recent discovery and is not yet well understood. In order to fill the gap on how substrate stiffness affects the molecular forces that stabilize biofilms, my lab will pioneer a three-way correlated measurements between scanning probe microscopy, optical microscopy, and force spectroscopy, with single-molecule and single-cell resolution. This quantitative and correlated approach to biofilm study will not only provide high-resolution images of the biofilm's complex structures, under physiological conditions, it will also quantify the nanoscale forces that stabilize these structures. The long-term goal is to expand the research to cover other substrate properties, and other biofilm-forming bacteria. This will provide a more general mechanistic insights into how the physico-chemical characteristics of the substrate influence the molecular forces that confer biofilm stability.Results from this research program will not only further our mechanistic understanding of the biofilm's structural stability in adhering to different surfaces, it will also lead to tangible benefits to Canadian industries related to agriculture, energy, environment, and public health, and to the global population, especially with the growing threat of antimicrobial-resistant organisms. Furthermore, with the interdisciplinary nature of the research it will be an excellent training ground for the next generation of Canadian scientists, and will bring Canada at the forefront of quantitative biofilm research.