Feng Liang, Yang Jixian, Ma Fang, Xing Lulu, Pi Shanshan, Cui Di, Li Ang
State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, People's Republic of China.
Engineering Research Center for Medicine, College of Pharmacy, Harbin University of Commerce, Harbin 150076, People's Republic of China.
Sci Total Environ. 2021 Jul 1;776:145939. doi: 10.1016/j.scitotenv.2021.145939. Epub 2021 Feb 17.
Certain metal ions can contribute to the functional microorganisms becoming dominant by stimulating their metabolism and activity. Therefore, Pseudomonas stutzeri T13 was used to investigate the impacts of biological stimulation with certain metal ions on aerobic denitrifying bacteria. Results showed that with the addition of 0.036 mmol/L Fe ions, the nitrogen-assimilation capacity of P. stutzeri T13 significantly increased by 43.99% when utilizing ammonium as the sole nitrogen source. Kinetic models were applied to analyze the role of Fe ions in the growth, and results indicated that increasing Fe ion concentrations decreased the decay rate. The maximum nitrate reduction rate increased from 9.55 mg-N L h to 19.65 mg-N L h with Fe ion concentrations increasing from 0.004 to 0.036 mmol/L, which was due to the increased level of napA gene transcription and activity of nitrate reductase. This study provides a theoretical foundation for further understanding of the mechanism of Fe ion stimulation of aerobic denitrification, benefiting the practicable application of aerobic denitrifiers.
某些金属离子可通过刺激功能微生物的新陈代谢和活性，使其成为优势菌。因此，本研究以施氏假单胞菌T13为研究对象，考察特定金属离子生物刺激对好氧反硝化细菌的影响。结果表明，在以铵为唯一氮源时，添加0.036 mmol/L铁离子后，施氏假单胞菌T13的氮同化能力显著提高了43.99%。采用动力学模型分析铁离子在生长过程中的作用，结果表明，增加铁离子浓度可降低衰减速率。随着铁离子浓度从0.004 mmol/L增加到0.036 mmol/L，最大硝酸盐还原速率从9.55 mg-N L h增加到19.65 mg-N L h，这是由于napA基因转录水平和硝酸盐还原酶活性增加所致。本研究为进一步了解铁离子刺激好氧反硝化作用的机制提供了理论基础，有利于好氧反硝化菌的实际应用。
