Biological nitrogen removal is a classic technique for removing nitrogen from wastewater that has been studied extensively and gives high nitrogen removal rate, energy efficiency, and is relatively environmentally benign. Using biological nitrogen removal processes to treat the diverse components of wastewater requires a thorough understanding of the microorganisms and pathways involved. However, information regarding the diverse microorganisms participating in nitrogen removal processes remains limited. This review presents the current knowledge of the researches into these microorganisms, including ammonia oxidizing bacteria, archaea, complete ammonia oxidation bacteria, nitrite-oxidizing bacteria, anaerobic ammonium oxidation bacteria, denitrifying bacteria, and heterotrophic nitrification-aerobic denitrification bacteria. The metabolic pathways and enzymatic reactions involved in nitrogen cycle of abovementioned microorganisms are demonstrated. The key enzymes, functional genes, and metabolic pathways of the nitrogen removal-related microorganisms were extensively discussed. Additionally, the advantages of the different microorganisms for the ammonia oxidation, denitrifying, and HN-AD are described. Finally, the limitations and strategies in unraveling the nitrogen metabolic pathways were presented. The aim of the review is to improve our understanding of the principle involved in advanced nitrogen removal processes to allow possible improvements to wastewater treatment processes to be identified.

中文翻译：

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脱氮相关微生物的关键酶、功能基因和代谢途径


生物脱氮是一种从废水中脱氮的经典技术，已被广泛研究，脱氮率高，能源效率高，并且相对环境无害。使用生物脱氮工艺处理废水中的不同成分需要对所涉及的微生物和途径有透彻的了解。然而，有关参与脱氮过程的各种微生物的信息仍然有限。本文综述了目前对这些微生物的研究知识，包括氨氧化细菌、古细菌、完全氨氧化细菌、亚硝酸盐氧化细菌、厌氧铵氧化细菌、反硝化细菌和异养硝化好氧反硝化细菌。证明了上述微生物参与氮循环的代谢途径和酶促反应。本文广泛讨论了脱氮相关微生物的关键酶、功能基因和代谢途径。此外，还描述了不同微生物在氨氧化、反硝化和 HN-AD 方面的优势。最后，提出了解开氮代谢途径的局限性和策略。审查的目的是提高我们对高级脱氮工艺所涉及原理的理解，以便确定废水处理工艺的可能改进。