Collaborative Research: Microbial Flocculation Dynamics

研究人员和他的同事们研究了水性，多细胞，微生物群落的种群动态。这些群落从实验室到海洋无处不在，本研究的目的是促进对微生物絮凝的理解，微生物絮凝是悬浮液中增殖的生物群碎片和聚集体的过程。具体而言，研究人员使用半群，分形，偏微分方程和计算分析来推进一类新的结构化人口模型的理论和应用。模型开发，分析和实验验证之间的密切耦合允许深入了解这种全球普遍存在的微生物存在的基本状态的生物力学和代谢适应。 研究者和他的同事们被三个激励性的问题所引导：1）驱动絮凝体破碎的主要机制是什么？ 2)絮凝体结构的变化如何影响种群增殖？ 和 3)为什么有些絮凝体的种群分布收敛到自相似性，而另一些则衰减到单分散性？对微尺度机制的深入了解可能会极大地改变微生物种群的建模和控制。悬浮在流体中的微生物通常不以单细胞形式存在-通过碰撞和分离，它们在称为絮凝的过程中联合收割机和重新联合收割机结合。这些微生物群落存在于从实验室到海洋的任何地方，絮凝的趋势对人类生活产生了惊人的影响。例如，基于细胞培养的工业生物技术（例如，在蛋白质作为药物的制造商中）严重依赖于对微生物群落的物理性质的预测。细菌群被用于全国各地的城市污水处理厂，作为清洁人类和工业废水的环境可持续部分。此外，流体中的细菌和藻类群落是生物塑料、生物燃料和沼气工业的重要组成部分。 在自然环境中，藻类的絮凝特性在藻类大量繁殖中起着重要作用（并因此产生负面的经济和健康影响）。研究人员和他的同事开发和研究絮凝的数学模型，并进行实验，以验证集群大小和增长率分布的预测。该项目旨在将对微生物絮凝的科学理解从基于简化的理想化集群模型转变为基于微尺度机械和代谢第一原理的模型。我们对这些微生物聚集体的种群行为的理解的进步可能会导致生物燃料生产效率，可持续处理废水的方法和海洋藻类水华管理等各种社会挑战的显着改善。

The investigator and his colleagues study the population dynamics of aqueous, multi-cellular, microbial communities. These communities are ubiquitous from the laboratory to the ocean, and the objective of this research is to advance understanding of microbial flocculation, the process whereby proliferating clusters of organisms in suspension fragment and aggregate. Specifically, the researchers use semigroup, fractal, partial differential equation, and computational analysis to advance the theory and applications for a novel class of structured population models. The close coupling between the model development, analysis, and experimental validation allows insight into the biomechanical and metabolic adaptations of this globally pervasive and fundamental state of microbial existence. The investigator and his colleagues are guided by three motivating questions: 1) what are the dominant mechanisms driving floc fragmentation? 2) How does floc structure variability impact population proliferation? and 3) Why do some floc population distributions converge to self-similarity and others decay to mono-dispersion? Insight into the dominant microscale mechanisms could dramatically change both modeling and consequently control of microbial populations.Micro-organisms suspended in a fluid often do not live as single cells - by collision and separation they combine and recombine in a process called flocculation. These microbial communities exist everywhere from the laboratory to the ocean and the tendency to flocculate has a surprising impact on human life. For example, industrial biotechnologies based on cell cultures (e.g., in the manufacturer of proteins as drugs) rely heavily on predictions of the physical properties of microbial communities. Bacterial clusters are used in municipal sewage treatment plants across the country as an environmentally sustainable part of cleaning human and industrial wastewater. Moreover, bacterial and algal communities in a fluid are an essential part of the bioplastic, biofuel, and biogas industries. In natural settings, the flocculation properties of algae play an important role in algal blooms (and thus in the resultant negative economic and health impacts). The investigator and his colleagues develop and study mathematical models of flocculation and perform experiments to validate predictions of the distribution of cluster sizes and growth rates. This project aims to transform scientific understanding of microbial flocculation from one based upon simplified, idealized models of clusters to one based on microscale mechanistic and metabolic first principles. Advances in our understanding of the population behavior of these microbial aggregates could lead to dramatic improvements in such diverse societal challenges as biofuel production efficiency, sustainable means of handling wastewater, and management of oceanic algal blooms.