[Design and application of artificial multicellular systems for nitrogen removal from wastewater]

Excessive accumulation of nitrogen is a major cause of water eutrophication. Developing an inexpensive and efficient nitrogen removal technology is therefore essential for wastewater purification. The microbial technology for nitrogen removal has been widely used for its low cost, high efficiency, and strong environmental adaptability. Most recently, with the advances in synthetic biotechnology, artificial multicellular systems have been sufficiently developed and exhibited unique definability and controllability. Compared with those in the natural microbial consortia, the nitrogen removal pathways and environmental response mechanisms are easy to be clarified in the artificial multicellular systems, which allow for efficient nitrogen removal under low cellular metabolic loading. Therefore, artificial multicellular systems demonstrate great application potential in the purification of wastewater, including landfill leachate, industrial wastewater, seawater aquaculture wastewater, and domestic sewage. We focused on the design, building, and application of artificial multicellular systems for nitrogen removal from wastewater. Specifically, we summarized the functional microorganisms and their nitrogen removal mechanisms, introduced the design principles and building methods of artificial multicellular systems, illustrated the application of artificial multicellular systems with examples, and prospected the future research trend in nitrogen removal from wastewater. The conclusion is expected to provide new insights and efficient strategies for optimizing the microbial nitrogen removal from wastewater.