Collaborative Research: Elucidating the Diversity of Bacterial Flagellation and Motility Through Mechanics

合作研究：通过力学阐明细菌鞭毛和运动的多样性

基本信息

批准号：
2027410
负责人：
Jeffrey Guasto
金额：
$ 31.25万
依托单位：
Tufts University
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2021
资助国家：
美国
起止时间：
2021-01-01 至 2024-12-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=2027410&HistoricalAwards=false
关键词：
Collaborative Research Elucidating Diversity Bacterial

项目摘要

The ability of bacteria to swim crucial to survival. Swimming is made possible by rotating thin filaments called flagella. There are many different ways that flagella are arranged on bacteria, and many different movement patterns, all of which enable swimming. Despite the success of bacteria swimming, few of these mechanisms are well understood. The objective of this project is to determine how the arrangements and flexible mechanics of flagella combine to produce differences in bacterial motility. The results of this project will have numerous potential societal impacts, since motility enables bacteria to spread through water supplies, and to establish microbiomes or infections in humans. This work will have important effects at multiple levels. At the cellular level, better understanding bacterial motility will help us understand cell resource uptake. At the ecosystem scale, motility affects the food web. The results of this work could lead to new approaches to mediate bacterial infection, further our understanding of bacterial evolution, and inspire biomimetic microrobots with enhanced functionality. In addition, the award will support outreach programs that teach the public about bacterial locomotion and its importance to society through health and ecology.Bacterial flagellar motility has largely been relegated to two idealized paradigms for uni- and multiflagellated cells, respectively. However, mounting evidence suggests that bacteria exhibit a plethora of flagellar arrangements and associated motility patterns that do not fit into the existing paradigms. It is not understood how flagellar motility patterns emerge from variations in arrangements and the flexible mechanics of flagella. This work will develop a mechanistic understanding of the vast understudied diversity of flagellar arrangements and motility patterns by linking them to the geometry and mechanics of flagella. This biomechanical understanding has been hindered by a lack of quantitative imaging of flagella, limited ability to experimentally perturb flagellar properties, and overly simplified models. We will overcome these challenges by using unique imaging capabilities, which enable data-driven and experimentally validated numerical modeling and hypothesis testing. Experimentally, this work incorporates advanced high-speed video microscopy techniques to capture the time-resolved kinematics of 10-nanometer diameter flagella, pushing the envelope of existing quantification methods for fluid-structure interactions. Numerically, this work advances the state-of-the-art in modeling elastohydrodynamics of actuated filaments. This work will establish a unique data set comprising the mechanical properties of flagella and the kinematics of bacterial motility from diverse species. It will use modeling to determine the physical mechanisms leading to observed motility patterns, and combine physical and numerical experiments to elucidate and classify the originsThis award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

细菌游泳对生存至关重要的能力。通过旋转称为鞭毛的细丝，使游泳成为可能。鞭毛在细菌和许多不同的运动模式上排列在许多不同的方式中，所有这些方式都可以游泳。尽管细菌游泳取得了成功，但这些机制中很少有很好的了解。该项目的目的是确定鞭毛的布置和柔性力学如何相结合以产生细菌运动的差异。该项目的结果将产生许多潜在的社会影响，因为运动能够使细菌通过供水传播，并在人类中建立微生物组或感染。这项工作将在多个层面上产生重要影响。在细胞水平上，更好地了解细菌运动能力将有助于我们了解细胞资源的吸收。在生态系统量表上，运动会影响食物网。这项工作的结果可能会导致新的介导细菌感染的方法，进一步我们对细菌进化的理解，并激发具有增强功能的仿生微生物。此外，该奖项将支持宣传计划，这些计划向公众传授细菌的运动及其对社会的重要性。基本的鞭毛运动在很大程度上已被降级为两个理想化的单一和多斑点细胞的理想范式。但是，越来越多的证据表明，细菌表现出许多不适合现有范式的鞭毛布置和相关的运动模式。尚不理解鞭毛运动模式如何从布置和柔性力学的变化中出现。这项工作将通过将它们与鞭毛的几何形状和机制联系起来，对鞭毛布置和运动模式的大量研究的机械理解。由于缺乏对鞭毛的定量成像，有限的实验性鞭毛特性和过度简化模型的能力，这种生物力学理解受到了阻碍。我们将通过使用独特的成像功能来克服这些挑战，从而实现数据驱动和实验验证的数值建模和假设测试。在实验上，这项工作结合了先进的高速视频显微镜技术，以捕获10纳米直径的时间分辨的运动学动力学，从而推动了用于流体结构相互作用的现有量化方法的信封。从数值上讲，这项工作在对驱动细丝的弹性水力动力学进行建模方面提高了最新的作用。这项工作将建立一个独特的数据集，其中包括鞭毛的机械性能以及来自不同物种的细菌运动的运动学。它将使用建模来确定导致观察到的运动模式的物理机制，并结合物理和数值实验，以阐明和分类这一奖项，这反映了NSF的法定任务，并被认为是通过基金会的智力优点和更广泛的影响审查标准来通过评估来进行评估的。