城市污水处理厂活性污泥中地杆菌分布特征和作用机制的研究

The activated sludge process is still at the heart of current sewage treatment technology. The structure and function of microbial community in activated sludge decide the treatment efficiency and operational performance of sewage treatment plant. The aerobic characteristics of activated sludge process determine that microorganisms are generally strictly aerobic or facultative anaerobic, few strict anaerobic bacteria can survive and function in activated sludge. Based on the unexpected findings that high abundance of strict anaerobic bacteria-Geobacter were detected in activated sludge from municipal sewage treatment plants, this project intends to carry out the research on distribution feature and interaction mechanism of Geobacter in activated sludge. Specific interests are placed on exploring the temporal and spatial distribution of Geobacter in activated sludge from municipal sewage treatment plants, analyzing the key environmental factors affecting the distribution of Geobacter in activated sludge, uncovering the mechanism of oxygen resistance by Geobacter under aerobic conditions, evaluating the biodegradability of different types of contaminants in activated sludge by Geobacter, and studying the interaction mechanism between Geobacter and other microorganisms in activated sludge. The results generated from this research can provide theoretical guidance and technical support for the further clarification on the microbial characteristics in activated sludge from municipal sewage treatment plants and the optimization and upgrading of pollutant removal performance by activated sludge process.

活性污泥法是迄今为止应用最广泛的废水生物处理工艺，活性污泥中微生物菌群的结构和功能决定了污水处理厂的处理效果和运行效能。活性污泥工艺需氧的特点决定其中的微生物一般均为严格好氧或者兼性厌氧生长，因而鲜有严格厌氧菌在活性污泥中存活和发挥功能的报道。基于申请人有关城市污水处理厂活性污泥中含有较高丰度的严格厌氧菌-地杆菌（Geobacter）的意外发现，本项目拟开展活性污泥中地杆菌分布特征和作用机制的研究，探索城市污水处理厂活性污泥中地杆菌的时、空分布规律，分析影响活性污泥中地杆菌分布的关键环境因子，解析地杆菌在好氧条件下的耐氧机制，评估地杆菌对活性污泥中不同类型污染物的降解性能，并研究活性污泥中地杆菌与其他微生物的相互作用机制，从而为进一步阐明城市污水处理厂活性污泥的微生物特征、优化和提升活性污泥的污染物处理性能提供理论指导和技术支持。

活性污泥法是迄今为止应用最广泛的废水生物处理工艺，活性污泥中微生物菌群的结构和功能决定了污水处理厂的处理效果和运行效能。活性污泥工艺需氧的特点决定其中的微生物一般均为严格好氧或者兼性厌氧生长，因而鲜有严格厌氧菌在活性污泥中存活和发挥功能的报道。基于申请人有关城市污水处理厂活性污泥中含有较高丰度的严格厌氧菌-地杆菌（Geobacter）的意外发现，本项目探明了城市污水处理厂活性污泥中地杆菌的时空分布特征，发现营养条件是决定地杆菌在城市污水处理厂活性污泥中分布规律的关键因子；针对地杆菌严苛的生长条件以及复杂的电子传递网络，建立了地杆菌高效的基因编辑系统，揭示了参与地杆菌氧化应激过程中关键的酶和基因；评估了地杆菌对芳烃类、偶氮染料类、重金属类污染物的降解性能；解析了地杆菌通过直接电子传递介导种间相互作用从而参与环境污染物的转化过程。在环境领域最有影响力的刊物Environmental Science & Technology（5 篇）、 Environmental Microbiology （2 篇）、Biotechnology and Bioengineering（3 篇）等上共发表了21 篇文章，协助课题组培养了3名博士研究生。