State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China.
Sci China Life Sci. 2018 Jul;61(7):753-761. doi: 10.1007/s11427-017-9228-2. Epub 2018 Jan 9.
Nitrogen pollution is an increasingly severe worldwide problem because of drainage of nitrogen-containing wastewater and intensive application of nitrogen-containing fertilizers. Denitrification, a key process in nitrogen cycles, is commonly employed for nitrogen removal in engineered wastewater treatment systems. Biological denitrification is performed by denitrifying microbes (bacteria) that use nitrate as terminal electron acceptor. Better understanding the functions of diverse microbial populations in denitrification-based wastewater treatment systems, and the interactions of these populations with operating environments, is essential for improving both treatment performance and system stability. Recent advances in "meta-omics" (e. g., genomics, transcriptomics, proteomics, metabolomics), other molecular biology tools, and microbiome analysis have greatly enhanced such understanding. This minireview summarizes recent findings regarding microbial community structure and composition, key functional microbes and their physiology, functional genes involved in nitrogen cycle, and responses of microbes and their genes to changes of environmental factors or operating parameters, in denitrification processes in wastewater treatment systems. Of particular interest are heterotrophic denitrification systems (which require alternative organic carbon sources) and the autotrophic denitrification systems (which do not require an external carbon source). Integrated microbiome and -omics approaches have great future potential for determination of optimal environmental and biotechnological parameters, novel process development, and improvement of nitrogen removal efficiency and system stability.
氮污染是一个日益严重的全球性问题，这是由于含氮废水的排放和含氮肥料的大量使用。反硝化作用是氮循环中的一个关键过程，常用于工程化废水处理系统中的氮去除。生物反硝化是由反硝化微生物（细菌）完成的，它们使用硝酸盐作为末端电子受体。更好地了解不同微生物种群在基于反硝化的废水处理系统中的功能，以及这些种群与运行环境的相互作用，对于提高处理性能和系统稳定性至关重要。“宏基因组学”（例如基因组学、转录组学、蛋白质组学、代谢组学）、其他分子生物学工具和微生物组分析等方面的最新进展极大地促进了这种理解。本文综述了最近在废水处理系统中反硝化过程中微生物群落结构和组成、关键功能微生物及其生理学、参与氮循环的功能基因，以及微生物及其基因对环境因素或运行参数变化的响应方面的发现。特别关注的是异养反硝化系统（需要替代有机碳源）和自养反硝化系统（不需要外部碳源）。综合微生物组学和组学方法在确定最佳环境和生物技术参数、开发新过程以及提高氮去除效率和系统稳定性方面具有巨大的未来潜力。
