硫自养型DNRA-厌氧氨氧化完全自养体系构建与同步脱氮除硫机制解析

尽管已有超过100个厌氧氨氧化处理厂在运行，厌氧氨氧化的应用依然受限于硝氮积累导致的总氮去除率低的瓶颈科学问题。研究发现硫自养型DNRA菌（S-DNRA）与厌氧氨氧化菌在自然生境中共存，且从反应热力学角度S-DNRA比同型反硝化有优势。本项目将通过S-DNRA转化厌氧氨氧化生成的硝氮，同步去除前序厌氧消化产生的硫化物，构建S-DNRA-厌氧氨氧化完全自养体系，在提高总氮去除的同时实现同步脱氮除硫；筛选最优自养体系构建策略，优化体系运行条件；采用同位素示踪、化学计量学等方法研究同步脱氮除硫体系中氮、硫的迁移转化途径；利用高通量和宏基因组测序等分子生物学手段解析微生物群落结构和演替，结合pMENs分析和蛋白质组学，从群落、酶学和蛋白水平上阐明S-DNRA-厌氧氨氧化自养体系同步脱氮除硫的机制。项目成果可有效提高总氮去除、减缓前序工艺产生硫离子的生物毒性，促进厌氧氨氧化和DNRA工艺的应用推广。

Although more than 100 anaerobic ammonium oxidation (anammox) treatment plants are already in operation, the application of anammox is still limited by the bottleneck scientific problem of low total nitrogen removal rate caused by effluent nitrate accumulation. Sulfur autotrophic dissimilation nitrate reduction to ammonium (S-DNRA) bacteria coexist with anammox bacteria in natural habitats, and sulfur autotrophic DNRA has a competitive advantage over autotrophic denitrification from the perspective of reaction thermodynamics. This project will adopt S-DNRA to reduce nitrate produced by anammox, and simultaneously remove sulfide produced by anaerobic digestion. A new S-DNRA-anammoxn complete autotrophic system will be established to improve the total nitrogen removal, achieving simultaneous nitrogen and sulfur removal. The optimal strategy to construct the complete autotrophic system will be screened and the system operating conditions will be optimized. The pathways of nitrogen and sulfur transformation in simultaneous nitrogen and sulfur removal system will be revealed by isotopic tracing technique and stoichiometry. The diversity and succession of microbial communities will also be studied by molecular biological techniques such as high-throughput and metagenomic sequencing in this project. Combined with phylogenetic molecular ecological networks (pMENs) analysis and proteomics, the enhanced nitrogen and sulfur removal mechanism in the simultaneous nitrogen and sulfur removal system will be revealed from community, enzymology and protein levels. This project can promote the total nitrogen removal of anammox. At the same time, the biological toxicity of sulfur ion from the anaerobic digestion can be alleviated. The results may promote the application and spread of anammox and DNRA process.