School of Civil Engineering, Changan University, Xian, China; Key Laboratory of Water Supply & Sewage Engineering, Ministry of Housing and Urban-rural Development, China; Chang'an University, The Middle Section of the South 2nd Ring Road, 710064, Xian, Shaanxi Province, China.
School of Water and Environment, Changan University, Xian, China; Chang'an University, The Middle Section of the South 2nd Ring Road, 710064, Xian, Shaanxi Province, China.
Chemosphere. 2024 Aug;361:142525. doi: 10.1016/j.chemosphere.2024.142525. Epub 2024 Jun 3.
Pseudomonas sp. ZHL02, removing nitrogen via ammonia nitrogen (NH) → hydroxylamine (HNOH) → nitrite (NO) → nitrate (NO) → NO → nitric oxide (NO) → nitrous oxide (NO) pathway was employed for getting in-depth information on the heterotrophic nitrification-aerobic denitrification (HNAD) pathway from carbon oxidation, nitrogen conversion, electron transport process, enzyme activity, as well as gene expression while sodium succinate, sodium citrate, and sodium acetate were utilized as the carbon sources. The nitrogen balance analysis results demonstrated that ZHL02 mainly removed NH-N through assimilation. The carbon source metabolism resulted in the discrepancies in electron transport chain and nitrogen removal between different HNAD bacteria. Moreover, the prokaryotic strand-specific transcriptome method showed that, amo and hao were absent in ZHL02, and unknown genes may be involved in ZHL02 during the HNAD process. As a fascinating process for removing nitrogen, the HNAD process is still puzzling, and the relationship between carbon metabolism and nitrogen metabolism among different HNAD pathways should be studied further.
采用假单胞菌 ZHL02 通过氨氮 (NH) →羟胺 (HNOH) →亚硝酸盐 (NO) →硝酸盐 (NO) →一氧化氮 (NO) →一氧化二氮 (NO) 途径去除氮，深入了解从碳氧化、氮转化、电子传递过程、酶活性以及基因表达等方面的异养硝化-好氧反硝化 (HNAD) 途径，同时利用琥珀酸钠、柠檬酸钠和乙酸钠作为碳源。氮平衡分析结果表明，ZHL02 主要通过同化作用去除 NH-N。碳源代谢导致不同 HNAD 细菌之间的电子传递链和氮去除存在差异。此外，原核链特异性转录组方法表明，ZHL02 中不存在 amo 和 hao，并且在 HNAD 过程中可能涉及未知基因。作为一种去除氮的迷人过程，HNAD 过程仍然令人费解，不同 HNAD 途径之间的碳代谢和氮代谢之间的关系应进一步研究。
