摘要
      抗生素和抗生素耐药性基因（ARGs）已被公认为人类和动物健康的新高危污染物。本研究系统地研究了畜禽养殖废水中一种典型抗生素（磺胺二脒，SDM）对厌氧氨氧化过程的综合影响，旨在阐明厌氧氨氧化联合体对抗生素应激的细胞内和细胞外保护机制。结果表明，高浓度SDM显著降低了比厌氧氨氧化活性（SAA）37.8%。Kuenenia Candidatus的丰度变化与SAA的丰度变化趋势相似，而其他与氮相关的微生物（如硝化单胞菌和硝化螺旋菌）对氮的去除有贡献，尤其是在抑制期。厌氧氨氧化菌群对SDM的抵抗主要取决于ARGs和EPS的保护。网络分析显示，eARGs的宿主范围相对大于iARGs，并且intI1与具有代表性的反硝化菌密切相关。此外，化蛋白质组学分析和分子对接结果表明，EPS中丰富的蛋白质可以通过氢键形成复合物将SDM滞留在细胞外基质中。这些发现为厌氧氨氧化过程的稳定运行和ARGs的转移控制提供了指导。
Abstract
Antibiotics and antibiotic resistance genes (ARGs) have been recognized as emerging high-risk pollutants for human and animal health. This study systematically investigated the comprehensive effects of a typical antibiotic (sulfadimidine, SDM) in livestock and poultry breeding wastewater on the anammox process, with the aim of elucidating the intracellular and extracellular protective mechanisms of the anammox consortia to the antibiotic stress. Results revealed that the high-concentration SDM significantly reduced the specific anammox activity (SAA) by 37.8%. Changes in the abundance of Candidatus Kuenenia showed a similar trend with that of SAA, while other nitrogen-related microorganisms (e.g., Nitrosomonas and Nitrospira) contributed to the nitrogen removal especially during the inhibitory period. Resistance of the anammox consortia to SDM mainly depended on the protection of ARGs and EPS. Network analysis revealed the host range of eARGs was relatively larger than that of iARGs, and intI1 was closely associated with representative denitrifiers. In addition, metaproteomic analysis and molecular docking results indicated that abundant proteins in EPS could detain SDM in the extracellular matrix through forming complex via hydrogen bond. These findings provide a guidance for the stable operation of anammox process and ARGs transfer controlling.

https://www.sciencedirect.com/science/article/abs/pii/S0304389422006069