Guo Mengyang, Liu Kai, Wang Hongfei, Song Yilin, Li Yingying, Zhang Weijin, Gao Jian, Liao Mingjun
Hubei Key Laboratory of Environmental Geotechnology and Ecological Remediation for Lake & River, Hubei University of Technology, Wuhan 430068, China.
Key Laboratory of Intelligent Health Perception and Ecological Restoration of Rivers and Lakes, Ministry of Education, Hubei University of Technology, Wuhan 430068, China.
Microorganisms. 2025 May 30;13(6):1274. doi: 10.3390/microorganisms13061274.
To date, the nitrogen metabolism pathways and salt-tolerance mechanisms of halophilic denitrifying bacteria have not been fully studied, and full-scale engineering trials with saline fly ash-washing wastewater have not been reported. In this study, we isolated and screened a halophilic denitrifying bacterium ( sp.), GH-1, analyzed its nitrogen metabolism pathways and salt-tolerance mechanisms using whole-genome data, and explored its nitrogen removal characteristics under both aerobic and anaerobic conditions at different salinity levels. GH-1 was then applied in a full-scale engineering project to treat saline fly ash-washing leachate. The main results were as follows: (1) Based on the integration of whole-genome data, it is preliminarily hypothesized that the strain possesses complete nitrogen metabolism pathways, including denitrification, a dissimilatory nitrate reduction to ammonium (DNRA), and ammonium assimilation, as well as the following three synergistic strategies through which to counter hyperosmotic stress: inorganic ion homeostasis, organic osmolyte accumulation, and structural adaptations. (2) The strain demonstrated effective nitrogen removal under aerobic, anaerobic, and saline conditions (3-9%). (3) When applied in a full-scale engineering system treating saline fly ash-washing wastewater, it improved nitrate nitrogen (NO-N), total nitrogen (TN), and chemical oxygen demand (COD) removal efficiencies by 31.92%, 25.19%, and 31.8%, respectively. The proportion of sp. increased from 0.73% to 3.41% (aerobic stage) and 2.86% (anoxic stage). Overall, halophilic denitrifying bacterium GH-1 can significantly enhance the nitrogen removal efficiency of saline wastewater systems, providing crucial guidance for biological nitrogen removal treatment.
迄今为止，嗜盐反硝化细菌的氮代谢途径和耐盐机制尚未得到充分研究，且尚未见有关于处理含盐粉煤灰洗涤废水的全规模工程试验报道。在本研究中，我们分离并筛选出一株嗜盐反硝化细菌（菌株）GH-1，利用全基因组数据分析其氮代谢途径和耐盐机制，并探究其在不同盐度水平下有氧和厌氧条件下的脱氮特性。随后将GH-1应用于处理含盐粉煤灰洗涤渗滤液的全规模工程项目中。主要结果如下：（1）基于全基因组数据整合，初步推测该菌株具有完整的氮代谢途径，包括反硝化作用、异化硝酸盐还原为铵（DNRA）和铵同化作用，以及以下三种应对高渗胁迫的协同策略：无机离子稳态、有机渗透调节剂积累和结构适应。（2）该菌株在有氧、厌氧和含盐条件下表现出有效的脱氮效果（3-9%）。（3）当应用于处理含盐粉煤灰洗涤废水的全规模工程系统时，它分别提高了硝酸盐氮（NO-N）、总氮（TN）和化学需氧量（COD）的去除效率31.92%、25.19%和31.8%。该菌株的比例从0.73%增加到3.41%（好氧阶段）和2.86%（缺氧阶段）。总体而言，嗜盐反硝化细菌GH-1可显著提高含盐废水系统的脱氮效率，为生物脱氮处理提供关键指导。
