Harnessing Microbial Ecology for the Inhibition of Opportunistic Pathogens in Premise Plumbing

PI：Amy Pruden Proposal编号：CBET-1033498机构：弗吉尼亚理工大学题目：利用微生物生态学抑制房屋(即建筑)管道中的机会性病原体居住在房屋(即建筑)管道中的机会性病原体，如嗜肺军团菌、禽分枝杆菌、多食棘阿米巴和铜绿假单胞菌，现在是发达国家水源性疾病的主要原因。由于这些病原体在住宅管道系统内繁殖，而不是从处理厂排放，因此需要改变模式来减轻这一威胁。具体地说，PI坚持认为，微生物在房屋卫浴系统中是不可避免的，它们的活动可能是有益的。一种变革性的研究方法将探索利用微生物生态来抑制病原体增殖的可行性。最重要的假设是，将有益的微生物接种到前提管道系统中，可以抑制机会性病原体的建立和生长能力。此外，水处理和分配系统材料自然会产生接种物，这些接种物会不断地引入到建筑给水系统中，并且对这些因素如何选择有基本的理解？因为有益的生物体可以被自来水公司和监管机构利用来预防水媒疾病。这项研究的具体目标是：1)描述水处理、自来水管道材料和供水系统运行之间的相互作用，以选择有潜力抑制住宅卫浴系统中条件致病菌生长的微生物群落；2)通过开发和应用病原体再生长潜力分析，量化这些选择剂在住宅卫浴系统中可能遇到的极端再生长潜力下抑制病原体生长的程度；以及3)进行现场调查，将建筑物入口点的微生物生态与营养水平、先前的水处理和供水系统材料联系起来，并验证微生物生态和病原体再生长潜力之间的关系。预计不同的管道材料、可同化有机碳浓度、消毒剂残留物和水龄将选择不同的微生物，这些微生物的内在能力不同，以抑制或放大场所管道系统中的机会性病原体。此外，将确定在水处理和分配过程中选择有益接种剂的统一因素，并与现场实际发病率相关。PIS认为，所提出的益生菌概念从未被应用于管道系统中的病原体控制，尽管它已在医学和腐蚀研究中得到证明。此外，将水处理厂和分配系统视为具有理想特性的微生物生态选择器，建立在废水处理领域类似方法的成功基础上，同时也是实际可行的。实验设计提供了对推动房屋管道中机会性病原体扩散的化学和微生物因素的全面了解，这对于合理制定未来的缓解策略至关重要。预计其他学科将受到影响，特别是生物膜和病原体生态学。这项研究将通过解决发达国家水媒疾病的主要来源，并帮助澄清公用事业与个人在管理病原体生长方面的相对作用/责任，从而使社会受益。拟议的机会性病原体再生潜力分析代表了一个实际结果，其应用超出了拟议工作的范围，因为它可以用于比较病原体、再生潜力？不同的水域。这些结果还有望解释，即使在同一座城市，不同社区因室内管道病原体而感染水源性疾病的可能性是如何随着水龄、氯胺残留和与不同管道材料相关的微生物生态而变化的。两名研究生研究助理将得到该项目的支持，并将为REUS寻求补充资金。此外，还将开展实践活动，并将其提供给高中夏令营(如CTech2和NASA INSPIRE)，重点是招募妇女进入STEM领域。PIS还将通过NTMir，Inc.接触受到机会性病原体直接影响的社区和个人，与美国环境保护局的科学家合作，并与Blacksburg和Pinellas Country合作，支持对实际分销系统中病原体再生潜力的评估。

PI: Amy PrudenProposal Number: CBET-1033498Institution: Virginia TechTitle: Harnessing Microbial Ecology for the Inhibition of Opportunistic Pathogens in Premise PlumbingOpportunistic pathogens residing in premise (i.e., building) plumbing; such as Legionella pneumophila, Mycobacterium avium, Acanthamoeba polyphaga, and Pseudomonas aeruginosa, are now the leading cause of waterborne disease in developed countries. Because these pathogens multiply within premise plumbing systems, rather than emanate from treatment plants, a paradigm shift is required to mitigate this threat. Specifically, the PIs maintain that microbes are unavoidable in premise plumbing systems and their activity can be beneficial. A transformative research approach will investigate the feasibility of harnessing microbial ecology to inhibit pathogen proliferation. The overarching hypothesis is that inoculation of beneficial microbes into premise plumbing systems can serve to inhibit the ability of opportunistic pathogens to establish and grow. Moreover, water treatments and distribution system materials naturally generate the inoculum that is continually introduced into premise plumbing systems, and a fundamental understanding of how these factors can ?select? for beneficial organisms could be exploited by water utilities and regulators to prevent waterborne disease. The specific objectives of this research are to: 1) Characterize the interplay between water treatment, water main pipe material, and water distribution system operation in selecting microbial communities with potential to inhibit growth of opportunistic pathogens in premise plumbing systems; 2) Quantify the extent to which these selectors can mitigate pathogen growth under extremes of regrowth potential that may be encountered in premise plumbing systems through development and application of a pathogen regrowth potential assay; and 3) Conduct a field survey linking microbial ecology at the point of entry of buildings to nutrient levels, prior water treatments and distribution system materials, and verify relationships between microbial ecology and pathogen regrowth potential. It is expected that various pipe materials, assimilable organic carbon concentrations, disinfectant residuals, and water ages will select for distinct microbes that vary in their inherent capabilities to inhibit or amplify opportunistic pathogens within premise plumbing systems. Furthermore, unifying factors that select for beneficial inocula during water treatment and distribution will be identified and related to actual incidence of disease in the field.The PIs believe that the probiotic concept proposed has never been applied to control of pathogens in plumbing systems, though it has been demonstrated in medical and corrosion studies. Furthermore, viewing water treatment plants and distribution systems as selectors of microbial ecology with desirable traits builds on the success of similar approaches in the wastewater treatment realm, while also being practically implementable. The experimental design provides a holistic understanding of chemical and microbiological factors driving the proliferation of opportunistic pathogens in premise plumbing, which is vital for rational development of future mitigation strategies. Other disciplines are anticipated to be impacted, biofilm and pathogen ecology, in particular.This study will benefit society by addressing the leading source of waterborne disease in developed countries and by helping to clarify the relative roles/responsibilities of utilities versus individuals in managing pathogen growth. The proposed opportunistic pathogen regrowth potential assay represents a practical outcome with applications beyond the scope of the proposed work, as it can be applied to compare the pathogen ?regrowth potential? of various waters. The results are also expected to explain how the likelihood of waterborne disease from premise plumbing pathogens varies from neighborhood to neighborhood even in the same city, as a function of water age, chloramines residual and microbial ecologies associated with different pipe materials. Two graduate research assistants will be supported by the project and supplemental funds will be sought for REUs. Additionally, hands-on activities will be developed and delivered to high school summer camps (e.g., CTech2 and NASA INSPIRE), with a particular focus on recruiting of women into STEM fields. The PIs will also engage in outreach to communities and individuals who have been directly impacted by opportunistic pathogens through NTMir, Inc., collaborate with scientists at the U.S. Environmental Protection Agency, and support evaluations of pathogen regrowth potential in real distribution systems in partnership with Blacksburg and Pinellas Country.