Bacterial trapping near topographic surfaces under shear flow

剪切流下地形表面附近的细菌截留

• 批准号: 462445093
• 负责人: Professor Dr. Holger Stark
• 金额: --
• 依托单位: Institut für Theoretische Physik
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/462445093?language=en
• 关键词: Bacterial; trapping; near; topographic; surfaces

Motile bacteria, such as Escherichia coli (E. coli), colonize surfaces, where they form hazardous biofilms and cause biofouling. When reaching the surface, they first need to be trapped by physical mechanisms, which then promotes their irreversible attachment to the surface through chemical bonding. Despite much insight, near-surface trapping of E. coli is still a poorly understood complex process, which is determined by E. coli’s run-and-tumble motility and physical conditions, such as shear flow and the surface topography. However, controlling near-surface trapping is essential for medical and biotechnological applications, for example, for preventing biofilms and biofouling but also for using bacteria as drug carriers to target disease sites such as malignant tumors. Therefore, the Indian and German groups join forces and use their complementary expertises to carry out a comprehensive simulation analysis in order to explore how physical conditions can be used to control the trapping of E. coli in shear flow near surfaces with different topography.We will perform a step-by-step analysis of the complex problem and heavily rely on a realistic model E. coli developed earlier by the Indian project leader. It will be used for a thorough preparatory analysis of the run-and-tumble motion in the bulk. In parallel, the German group will implement the model E. coli in a code based on the method of Multi-Particle Collision Dynamics, which will enable us to simulate fluid flows around the bacterium near surfaces with varying topography. Sharing the code between both groups, we will thoroughly analyze how a motile E. coli becomes trapped near a surface either in a quiescent fluid or under shear flow and thereby clarify contradicting observations. Our foci will be on the role of flagellar dynamics during runs and tumbles including polymorphism, which has so far been not resolved in any of the reported experimental studies on surface trapping, and also on the role of rheotaxis and Jeffery orbits for the bacterial dynamics. Finally, we will model surfaces with non-planar topography and investigate situations related to the control of biofouling and targeted drug deposition.

运动细菌，如大肠杆菌（E.大肠杆菌），定殖表面，在那里它们形成有害的生物膜并引起生物污垢。当到达表面时，它们首先需要被物理机制捕获，然后通过化学键促进它们不可逆地附着在表面上。尽管有很多见解，但E.大肠杆菌是一个复杂的过程，这是由大肠杆菌决定的。大肠杆菌的运行和翻滚运动和物理条件，如剪切流和表面形貌。然而，控制近表面捕获对于医学和生物技术应用是必不可少的，例如，用于防止生物膜和生物污垢，而且用于使用细菌作为药物载体以靶向疾病部位，例如恶性肿瘤。因此，印度和德国的小组联合起来，利用他们互补的专业知识，进行全面的模拟分析，以探索如何利用物理条件来控制E.大肠杆菌在不同地形表面附近的剪切流中的运动。我们将对这个复杂的问题进行一步一步的分析，并在很大程度上依赖于一个真实的大肠杆菌模型。由印度项目负责人早些时候开发的大肠杆菌。它将被用于对整体中的奔跑和翻滚运动进行彻底的预备分析。与此同时，德国集团将执行E模式。大肠杆菌在一个基于多粒子碰撞动力学方法的代码，这将使我们能够模拟流体流动的细菌附近的表面与不同的地形。在两个小组之间共享代码，我们将彻底分析一个运动E。大肠杆菌在静止流体或剪切流中被捕获在表面附近，从而澄清了相互矛盾的观察结果。我们的重点将是鞭毛动力学在运行和翻滚，包括多态性，迄今为止尚未解决的任何表面捕获的实验研究报告中的作用，也对rheotaxis和杰弗里轨道的细菌动力学的作用。最后，我们将模拟具有非平面形貌的表面，并研究与生物污垢和靶向药物沉积控制相关的情况。