固体碳源富集HN-AD菌体系碳代谢与氮转化机制

传统生物脱氮技术存在低温硝化和低碳反硝化两大瓶颈，无法满足城镇污水处理提标改造需求。异养硝化-好氧反硝化（HN-AD）菌具有极端环境耐受性能强、同步脱氮效率高等优势，而提升其在污水处理系统中的菌群竞争优势是实现工程应用的关键。申请人前期通过固体碳源负载实现了HN-AD菌高密度富集及生物强化效果，为深入解析该体系中的碳代谢、氮转化机制，拟开展以下研究：首先，构建HN-AD菌的富集体系，通过双响应值优化HN-AD菌脱氮效率和富集效果；其次，采用基因组、转录组、蛋白组和代谢组相结合的多组学模式，研究碳代谢和氮转化的主要代谢路径、酶学特征、功能基因和代谢产物，明确HN-AD菌利用固体碳源脱氮的作用机理；最后，借助高通量测序和微生物网络分析，研究强化系统中目标菌的优势变化及与其他功能菌的相互关系，解析强化菌落的演替规律。研究成果为水生态环境质量提升亟需的新型生物脱氮工艺研发提供理论依据和技术支撑。

Poor nitrification and denitrification performance of the traditional biological nitrogen removal technologies under low temperature and low carbon, respectively, become the bottleneck problems that limit the upgrading and reconstruction of municipal wastewater treatment plants. Heterotrophic nitrification-aerobic denitrification (HN-AD) has the advantages of strong extreme environmental tolerance and excellent simultaneous nitrification and denitrification performance. However, the competitive disadvantages of flora in bio-augmentation systems have always been a bottleneck hindering its engineering applications. More effective bio-enrichment method to make it more competitive in bio-augmentation system is the key to overcome this problem. It was noted that by using solid carbon source as fixed materials can achieve the enrichment of HN-AD bacteria, and a long-term and stable strengthening effect can be obtained by the bio-augmentation method of HN-AD bacteria pre-fixation instead of direct addition. In order to reveal the carbon metabolism and nitrogen transformation mechanisms of the enrichment system, the following researches are intended to be carried out: Firstly, constructing a enrichment system for HN-AD bacteria, optimizing the enrichment effect and nitrogen removal efficiency of HN-AD bacteria by double response value method. By using a multi-omics research model including genomes, transcriptomes, proteomics, and metabolomics, the main metabolic pathways, enzymatic characteristics, functional genes and metabolites during carbon metabolism and nitrogen transformation are studied, and the mechanism of HN-AD bacteria using solid carbon source for nitrogen removal is identified. Finally, high-throughput sequencing and microbial network analysis methods are used to obtain the abundance changes of target bacteria and the relations with other functional flora in the bio-augmentation systems, and to clarify the succession rule of the strengthening colony.The research results provide theoretical basis and technical support for the development of new biological nitrogen removal process that is urgently needed for improving the quality of aquatic ecological environment.