关键词: 异养硝化, 好氧反硝化, 氮素污染, 脱氮机制

Abstract: The nitrogen (N) pollution in water has become a serious problem for environment in China, and great effort has been taken to look for an efficient and economic method for N removal. In recent years, researchers have isolated many heterotrophic nitrifying and aerobic denitrifying bacteria from different environments. These functional bacteria showed tremendous potential for application by the reason of their rapid growth, simultaneously nitrifying and denitrifying under aerobic conditions and other organic pollutant removal. At present, the N removal pathway and mechanism of heterotrophic nitrification-aerobic denitrifying bacteria are mainly studied by assaying the intermediate or end product of N cycle, detecting the activity of related enzymes, annotating functional genes in N cycle and referring to the N cycle pathway of autotrophic nitrifying bacteria and anoxic denitrifying bacteria. The complete N conversion pathway and N metabolism mechanism should be further studied and determined. The progress on the related enzymes and their coding genes involved in N removal pathways of heterotrophic nitrification-aerobic denitrifying bacteria were summarized in order to provide reference for theoretical research of heterotrophic nitrifying-aerobic denitrifying bacteria and their application in wastewater denitrogenation.

Key words: heterotrophic nitrification, aerobic denitrification, nitrogen pollution, mechanism of nitrogen removal