CAREER: Dynamic Structure and Function of Biofilms for Wastewater Treatment

在美国，水和污水处理系统目前消耗了所有电能的3%到4%，升级污水处理（WWT）工厂以实现脱氮可能会使其能源需求增加一倍。除氮还可能大大增加一氧化二氮（N2O）的排放，这是一种强效温室气体。生物膜系统在升级除氮方面越来越受欢迎。一种新的生物膜方法是混合膜-生物膜工艺（HMBP），其中充满空气的膜支撑生物膜（MBfs）盒式集成到活性污泥池中。这消除了气泡曝气，潜在地节省了50%以上的污水处理电能需求，同时实现了氮的去除，并潜在地减少了N2O的排放。生物膜是动态系统，其中物理动力学（如分离）和化学动力学（如底物浓度变化）对生物膜的结构、功能和整体性能有重要影响。本研究旨在探讨生物膜在污水处理中的动态结构和功能。PI将开发一种新的实验方法，允许使用微传感器、用新型厌氧荧光蛋白标记的细菌和共聚焦激光扫描显微镜（CLSM）研究生物膜系统的物理和化学动力学。这允许近实时分析分离和底物浓度变化对生物膜结构和功能的影响。这项技术将用于研究不同分离模式（物理动力学）的影响，以及这如何影响生物膜的结构和功能，特别是当它们与HMBP过程相关时。PI还将研究生物膜中的N2O排放（化学动力学），以及它们如何受到氧浓度循环的影响。将开发多维的、基于粒子的模型来捕捉动态效果。本研究为生物膜研究开辟了一条新的途径。这些结果将为分离对生物膜的结构、功能和整体性能的影响提供一个基本的理解。这是第一次系统研究N2O在生物膜中的形成，以及生物膜的动态结构和功能。它使用了一种新的细菌组合，标记有厌氧荧光蛋白、CLSM和微传感器。最后，它还开发了一种新的、基于粒子的多维模型，适合于捕捉这些对生物膜的动态影响。该研究将直接影响对与污水处理相关的生物膜系统中分离和N2O形成的理解，包括基于mbf的应用。提出的研究平台可用于研究临床、工业和环境相关的生物膜，例如暴露于消毒剂、抗生素或重金属后的生物膜活力。该项目将重点培训和教育西班牙裔学生，鼓励他们从事科学和工程方面的职业。高中教师将接受培训，学会使用简单的分子工具，并在高中生的帮助下开发教学模块。启动与智利的本科生研究交流试点，为本科生和研究生提供国际研究经验。研究生也将参与国际研究合作。REU的学生将从波多黎各和当地拥有大量西班牙裔人口的大学招募

0954918NerenbergWater and wastewater systems currently consume 3% to 4% of all electrical energy production in the United States, and upgrading wastewater treatment (WWT) plants to achieve nitrogen removal may double their energy demands. Nitrogen removal also may substantially increase emissions of nitrous oxide (N2O), a potent greenhouse gas. Biofilm systems are increasingly popular for upgrades to nitrogen removal. A novel biofilm approach is the Hybrid Membrane-Biofilm Process (HMBP), where cassettes of air-filled membrane-supported biofilms (MBfs) are integrated into an activated sludge tank. This eliminates bubbled aeration, potentially saving over 50% of the electrical energy requirements for WWT, while achieving nitrogen removal and potentially minimizing N2O emissions. Biofilms are dynamic systems, where physical dynamics (e.g., detachment) and chemical dynamics (e.g., varying substrate concentrations) can have important effects on biofilm structure, function, and overall performance. The goal of this research is to investigate the dynamic structure and function of biofilms for WWT. The PI will develop a novel experimental approach that allows the study of physical and chemical dynamics of biofilm system using microsensors, bacteria tagged with a novel anaerobic fluorescent protein, and confocal laser scanning microscopy (CLSM). This allows near real-time analysis of the effects of detachment and shifts in substrate concentrations on the structure and function of biofilms. This technique will be used to study the effect of different modes of detachment (physical dynamic), and how this affects the structure and function of biofilms, especially as they relate to the HMBP process. The PI also will study N2O emissions in biofilms (chemical dynamic), and how they are affected by cycling of oxygen concentrations. Multi-dimensional, particle-based models will be developed to capture the dynamic effects. This research develops a novel approach to biofilm research. The results will provide a fundamental understanding of the effect of detachment on the structure, function, and overall performance of biofilms. It is the first systematic study of N2O formation in biofilms, and of the dynamic structure and function of biofilms. It uses a novel combination of bacteria tagged with anaerobic fluorescent proteins, CLSM, and microsensors. Finally, it also develops a novel, particle-based, multidimensional model suitable for capturing these dynamic effects on biofilms. The research will directly impact the understanding of detachment and N2O formation in biofilm systems relevant to WWT, including MBf-based applications. The proposed research platform can be used to study biofilms of clinical, industrial, and environmental relevance, such as biofilm viability after exposure to disinfectants, antibiotics, or heavy metals. The PI will focus on the training and education of Hispanic students to encourage them to pursue careers in science and engineering. High school teachers will be trained to use simple molecular tools and to develop teaching modules with assistance from high school students. A pilot undergraduate research exchange with Chile will be initiated as a means to provide an international research experience to undergraduate and graduate students. Graduate students also will be involved in international research collaborations. REU students will be recruited from Puerto Rico and local universities with large Hispanic populations