Shaanxi Provincial Field Scientific Observation and Research Station of Water Quality in Qinling Mountains, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China.
College of Environmental and Municipal Engineering, Lanzhou Jiaotong University, Lanzhou 730070, China.
Sci Total Environ. 2024 Dec 1;954:176614. doi: 10.1016/j.scitotenv.2024.176614. Epub 2024 Sep 30.
Reducing nitrate contamination in drinking water has become a critical issue in urban water resource management. Here a novel oligotrophic aerobic denitrifying bacterium, Pelomonas puraquae WJ1, was isolated and purified from artificial lake sediments. For the first time, excellent aerobic denitrification capabilities were demonstrated. At a carbon-to‑nitrogen ratio of 5.0, strain WJ1 achieved 100.0 % nitrate removal and 84.92 % total nitrogen removal within 24 h, with no nitrite accumulation. PCR amplification and sequencing confirmed the presence of the denitrification genes napA, nirS, and nosZ in the strain. The nitrogen balance demonstrated that approximately 74.95 % of the initial nitrogen was eliminated as gaseous products under aerobic conditions. Furthermore, carbon balance analysis showed that most electron donors from strain WJ1 were directed towards oxygen, with limited availability for nitrate reduction. A combination of bio-ECO analysis and network modeling indicated that strain WJ1 has robust metabolic capabilities for diverse carbon sources and exhibits high adaptability to complex carbon environments. Overall, Pelomonas puraquae WJ1 removed approximately 45.89 % of the nitrates in raw water, demonstrating significant potential for practical applications in oligotrophic denitrification.
在城市水资源管理中，减少饮用水中的硝酸盐污染已成为一个关键问题。本研究从人工湖底泥中分离纯化得到一株贫营养好氧反硝化菌，命名为 Pelomonas puraquae WJ1。首次证明了该菌具有良好的好氧反硝化性能。在碳氮比为 5.0 时，菌株 WJ1 在 24 h 内实现了 100.0%的硝酸盐去除率和 84.92%的总氮去除率，且无亚硝酸盐积累。PCR 扩增和测序结果证实该菌中存在反硝化基因 napA、nirS 和 nosZ。氮平衡表明，在好氧条件下，初始氮的约 74.95%以气态产物的形式被去除。此外，碳平衡分析表明，菌株 WJ1 的大部分电子供体都被导向氧气，用于硝酸盐还原的可用性有限。生物 ECO 分析和网络建模的组合表明，菌株 WJ1 具有对多种碳源的强大代谢能力，并对复杂的碳环境表现出很高的适应性。总的来说，Pelomonas puraquae WJ1 去除了原水中约 45.89%的硝酸盐，在贫营养型反硝化方面具有很大的实际应用潜力。
