The Role of Extracellular Polymeri Substances of Biofilm on Pathogen Disinfection in Water Distribution Systems

0933288Seo固定化的微生物细胞生长并产生胞外聚合物（EPS），其产生结构化的微生物群落。固定化细胞和EPS一起形成生物膜。来自美国许多自来水公司的报告表明，尽管消毒剂持续存在，生物膜仍在供水系统中存活，并对公众造成重大健康威胁。目前，给水管网中生物膜的持久性被认为与EPS密切相关。本提案的主要目的是了解给水管网中生物膜持续存在的机制。重点将放在了解生物膜EPS的作用，使用微电极技术和荧光标记探针原位生物膜监测。微电极技术和生物膜分析工具的拟议研究将拓宽我们对病原性生物膜形成及其消毒剂控制的理解。具体而言，这项研究将使定量评估的作用，EPS和生物膜结构上的运输和反应的消毒剂。这将导致与微电极和生物膜分析获得的建模参数的发展。此外，我们将确定EPS对病原体附着，分离和再分布的作用。最后，本研究将导致多个分布参数（水龄，反应性管道材料，磷缓蚀剂）对多物种生物膜生长的影响的综合评估。这项研究有新的关键方法，可以从以前的研究区分。首先，未回答的传输和反应动力学的二次消毒剂在生物膜将确定与新开发的微电极和原位生物膜分析。其次，将使用系统的方法来观察EPS对生物膜的分离和再分布的作用，监测分离的簇的生理状态，这不能用粒度分析仪来理解。除了扩大我们对学术界生物膜控制的理解外，拟议的研究对水务设施，工业和公共卫生产生了直接和广泛的影响。从这项研究中收集到的信息将使当地的供水公司，将生物膜控制策略，并提高我们目前的理解，在许多其他行业，包括医疗和化工行业的生物膜控制机制。这些结果将有助于通过改善饮用水对生物膜相关病原体感染的预防，并提供对EPS对抗抗菌药物作用的基本了解，从而有助于保护公共健康。此外，拟议的项目将导致两名博士生的培训和教育，本科生和高中生的夏季研究机会，以及将研究成果纳入PI三门本科课程的实施。

0933288SeoImmobilized microbial cells grow and produce extracelluar polymeric substance (EPS), which create structured communities of microorganisms. Together, immobilized cells and EPS form a biofilm. Reports from many water utilities in the US have shown that biofilm survives in water distribution systems despite the continuing presence of disinfectants and causes significant health threats to the public. Currently, the persistence of biofilm in water distribution systems is believed to be strongly related to EPS. The principal objective of this proposal is to understand the mechanisms of the persistence of biofilm in water distribution systems. Emphasis will be placed on understanding the role of biofilm EPS, using microelectrodes techniques and fluorescently labeled probes for in-situ biofilm monitoring. The proposed studies with microelectrodes techniques and biofilm analysis tools will broaden our understanding of pathogenic biofilm formation and its control with disinfectants. Specifically, this research will enable quantitative evaluation of the role of EPS and biofilm structure on the transport and reaction of disinfectants. This will result in the development of modeling parameters obtained with microelectrodes and biofilm analysis. In addition, we will identify the role of EPS on pathogen attachment, detachment and redistribution. Finally, this research will result in combined assessments of the effects of multiple distribution parameters (water age, reactive pipe material, phosphorous corrosion inhibitor) on multi-species biofilm growth. This research has new key approaches which can be differentiated from previous studies. First, the unanswered transport and reaction kinetics of secondary disinfectants in biofilm will be determined with newly developed microelectrodes and in-situ biofilm analysis. Second, a systematic approach will be used to observe the role of EPS on the detachment and redistribution of biofilm, monitoring physiological states of detached clusters which couldn't be understood with particle size analyzers. Beyond enlarging our understanding of biofilm control in academic society, the proposed research has direct and broad impacts on water utilities, industries, and public health. The information gleaned from this research will enable local water utilities to incorporate biofilm control strategies and enhance our current understanding of biofilm control mechanism in many other industries including medical and chemical industries. The outcomes will contribute to protecting public health by improving the prevention of biofilm related pathogen infection via drinking water and providing a fundamental understanding of the role of EPS against antimicrobial agents. In addition, the proposed project will result in the training and education of two Ph.D students, summer research opportunities for undergraduate and high school students, and implementation of research findings into PIs three undergraduate courses.