CAREER: Dynamic Structure and Function of Biofilms for Wastewater Treatment

Nerenberg水和废水系统目前消耗了美国全部电力生产的3%至4%，升级废水处理(WWT)厂以实现脱氮可能会使其能源需求增加一倍。脱氮还可能大幅增加一氧化二氮(N2O)的排放，一氧化二氮是一种强有力的温室气体。生物膜系统在脱氮方面的升级越来越受欢迎。一种新的生物膜方法是复合膜-生物膜工艺(HMBP)，即将充气的膜支撑生物膜(MBF)集成到活性污泥池中。这消除了鼓泡曝气，潜在地节省了WWT所需电能的50%以上，同时实现了脱氮，潜在地将N2O排放降至最低。生物膜是动态系统，其中物理动力学(如脱落)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。本研究的目的是研究WWT生物膜的动态结构和功能。PI将开发一种新的实验方法，允许使用微型传感器、标记了新型厌氧荧光蛋白的细菌和共聚焦激光扫描显微镜(CLSM)来研究生物膜系统的物理和化学动力学。这使得可以近乎实时地分析脱附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过程有关时。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气浓度循环的影响。将开发基于粒子的多维模型来捕捉动态效果。这项研究为生物膜的研究开辟了一条新的途径。这一结果将使我们从根本上理解分离对生物膜结构、功能和整体性能的影响。这是首次系统地研究生物膜中N2O的形成，以及生物膜的动态结构和功能。它使用了一种新型的细菌组合，标记了厌氧荧光蛋白、CLSM和微型传感器。最后，它还开发了一种新颖的、基于粒子的多维模型，适用于捕捉这些对生物膜的动态影响。这项研究将直接影响对与WWT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。所提出的研究平台可用于研究与临床、工业和环境相关的生物膜，例如接触消毒剂、抗生素或重金属后的生物膜生存能力。该协会将把重点放在对拉美裔学生的培训和教育上，以鼓励他们从事科学和工程方面的职业。高中教师将在高中生的帮助下接受使用简单分子工具和开发教学模块的培训。将启动与智利的试点本科生研究交流，作为向本科生和研究生提供国际研究经验的一种手段。研究生还将参与国际研究合作。REU的学生将从波多黎各和拥有大量拉美裔人口的当地大学招收

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