RII Track-4: NSF: Insights into Pathogenicity of Chlorine-Stressed Bacteria Using Combined In Vitro Assays and Metatranscriptomics

水中的细菌病原体对全球公共卫生构成重大威胁，特别是对免疫系统较弱的个体。目前，氯化是最广泛使用的水消毒过程，使水中微生物失活，以确保公众和环境健康。虽然水中的大多数细菌在加氯后可以有效地杀死，但有些细菌可能会因为对消毒剂的抵抗力而存活下来。目前还没有一项全面的研究来调查存活的细菌感染宿主并引起疾病的能力。该研究基础设施改善RII Track-4奖学金项目将探索水消毒对细菌致病性的影响，这将有助于克服目前在水处理后微生物风险评估方面的知识空白。这一目标将通过使用先进的细胞工具和下一代测序技术来实现，这些技术是在美国环境保护署生物测量处开发的。预计从该项目获得的基本知识将为利益攸关方和决策者提供有价值的信息，以重新评估目前的水处理工艺并减少健康风险。这项研究还将为新墨西哥州立大学（一所为西班牙裔服务的机构）中代表性不足的学生提供培训机会。这项研究基础设施改进轨道4 EPSCoR研究研究员（RII轨道4）提案将为新墨西哥州立大学的助理教授提供奖学金，并为研究生提供培训。这项工作将与位于俄亥俄州辛辛那提市的美国环境保护署（EPA）流域和生态系统特征处生物测量处的研究人员合作进行。了解消毒后存活的细菌是否仍保持其初始特征，特别是致病性，是至关重要的。不适当的氯化处理可能会通过诱导编码毒力、活性氧（ROS）反应的基因转录或毒力基因的水平转移来刺激存活细菌的致病性。本项目旨在通过研究宿主-细菌相互作用，更好地了解氯化后存活微生物的致病性。具体而言，本项目旨在：1)研究模拟胃肠道条件下氯应激菌的耐受性；2)检测氯应激菌对人肠上皮细胞的粘附和侵袭；3)比较非应激和氯应激细菌下细胞的炎症反应；4)利用多个qPCR阵列检测毒力基因表达的变化；5)通过全基因组转录分析阐明氯胁迫细菌对氯的细胞应答。该研究项目的预期成果将促进新型消毒策略的发展，以减少存活细菌的致病性，并最大限度地减少致病性细菌在配水系统中的传播。本研究开发的方法可扩展到食品保鲜和医用消毒剂领域。EPSCoR RII Track-4:NSF计划的支持将允许PI所在机构提高其研究能力，并与EPA建立合作网络。它还为PI的研究项目奠定了基础，使其成为水系统中病原体去除的重要和定期贡献者。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Bacterial pathogens in water pose a significant worldwide threat to public health, especially for individuals with weakened immune systems. Currently, chlorination is the most widely used water disinfection process to cause the inactivation of microorganisms in the water to ensure public and environmental health. While most bacteria in water can be effectively killed after chlorination, some may survive due to their resistance to disinfectants. There has yet to be a comprehensive study to investigate the ability of the surviving bacteria to infect a host and cause disease. This Research Infrastructure Improvement RII Track-4 fellowship project will explore the impact of water disinfection on the pathogenicity of bacteria, which will help overcome the current knowledge gap regarding microbial risk assessment after water treatment. This goal will be addressed by using advanced cellular tools and next-generation sequencing techniques developed at the host site, the Biological Measurements Branch of the US Environmental Protection Agency. The fundamental knowledge obtained from this project is expected to provide valuable information to stakeholders and policymakers for reassessing the current water treatment processes and reducing health risks. This research will also offer training opportunities for underrepresented students at New Mexico State University, which is an Hispanic-Serving Institution.This Research Infrastructure Improvement Track-4 EPSCoR Research Fellows (RII Track-4) proposal would provide a fellowship to an Assistant Professor and training for a graduate student at New Mexico State University. This work would be conducted in collaboration with researchers in the Biological Measurements Branch of the Watershed & Ecosystem Characterization Division at the United States Environmental Protection Agency (EPA) in Cincinnati, OH. Knowing if the surviving bacteria after disinfection still hold their initial characteristics, especially pathogenicity, is essential. There is a possibility that inappropriate chlorination may stimulate the pathogenicity of surviving bacteria due to the induced transcription of gene encoding virulence, reactive oxygen species (ROS) response, or horizontal transfer of virulence genes. This project aims to better understand the pathogenicity of surviving microorganisms after chlorination by investigating host-bacteria interactions. Specifically, this project aims to: 1) Investigate the tolerance of chlorine-stressed bacteria under simulated gastrointestinal conditions; 2) Examine the adhesion and invasion of chlorine-stressed bacteria to human intestinal epithelial cells; 3) Compare the inflammatory responses of cells under exposure to non-stressed and chlorine-stressed bacteria; 4) Determine the changes in virulence gene expression using multiple qPCR arrays; and 5) Elucidate cellular response of chlorine-stressed bacteria to chlorine through genome-wide transcriptional analysis. The expected outcomes of this fellowship project will facilitate the development of novel disinfection strategies to reduce the pathogenicity of surviving bacteria and minimize the spread of bacteria with pathogenicity into the water distribution system. The methods developed in the proposed study could be expanded to the fields of food preservation and medical disinfectants. The support from the EPSCoR RII Track-4:NSF program will allow the PI's institution to advance its research capacity and establish collaboration networks with EPA. It also provides a foundation for building the PI's research program into a significant and regular contributor to pathogen removal in water systems.This 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.