College of Resource and Environment, Northeast Agricultural University, Harbin 150030, China.
College of Resource and Environment, Northeast Agricultural University, Harbin 150030, China.
Bioresour Technol. 2023 Oct;386:129484. doi: 10.1016/j.biortech.2023.129484. Epub 2023 Jul 11.
To remove ammonium and tetracycline (TC) from wastewater, a new strain, DX-21, was isolated and exhibited simultaneous removal ability. The performance of DX-21 in TC removal, its removal mechanism, and the potential toxicities of the degradation products were investigated with genomics, mass spectrometry, density functional theory calculations, quantitative structure-activity relationship analyses, and Escherichia coli exposure experiments. DX-21 exhibited removal of ammonium (9.64 mg·L·h) via assimilation, and TC removal (0.85 mg·L·h) primarily occurred through cell surface bio-adsorption and biodegradation. Among the 12 identified degradation products, the majority exhibited lower toxicities than TC. Moreover, potential degradation pathways were proposed, including hydroxylation and deamination. Furthermore, DX-21 possessed TC resistance genes, various oxygenases and peroxidases that could potentially contribute to TC degradation. DX-21 colonized activated sludge and significantly enhanced the biodegradation of TC. Therefore, DX-21 showed potential for treating wastewater containing both ammonium and TC.
为了去除废水中的氨和四环素（TC），本研究分离到一株新的 DX-21 菌株，其具有同时去除这两种物质的能力。本研究利用基因组学、质谱、密度泛函理论计算、定量构效关系分析和大肠杆菌暴露实验，考察了 DX-21 对 TC 的去除性能、去除机制和降解产物的潜在毒性。DX-21 主要通过同化作用去除氨（9.64 mg·L·h），通过细胞表面生物吸附和生物降解去除 TC（0.85 mg·L·h）。在鉴定出的 12 种降解产物中，大多数的毒性均低于 TC。此外，还提出了潜在的降解途径，包括羟化和脱氨作用。此外，DX-21 还具有 TC 抗性基因、各种氧化酶和过氧化物酶，这些酶可能有助于 TC 的降解。DX-21 能够在活性污泥中定殖，并显著增强 TC 的生物降解。因此，DX-21 具有处理同时含有氨和 TC 的废水的潜力。
