摘要

    抗生素抗性基因（ARG）在环境中的广泛传播可能对公共健康构成严重威胁。废水处理厂（WWTP）被视为城市环境中ARGs的重要热点，但是事实证明，通过常规处理技术去除ARGs是不够的。在这项研究中，第一次应用高铁酸盐（Fe（VI））从污水处理厂的二级废水中去除细胞内ARG。结果表明，Fe（VI）处理可以有效去除覆盖8种不同类型的15种ARG和intI1，intl1是ARGs水平转移的最重要整合子。在Fe（VI）剂量为10 mg-Fe / L时，被测基因的去除效率可以达到1.10-4.37 log，这明显高于通过传统消毒方法获得的去除效率。 DNA凝胶电泳表明，Fe（VI）可能引起微生物DNA损伤，从而导致ARGs消除。在残留物中存在ARGs，这表明由Fe（VI）还原产物引发的凝结作用也有助于从废水中去除ARGs。此外，Fe（VI）处理后，废水中潜在的ARGs宿主的活力和相对丰度降低。这项研究表明，应用Fe（VI）有效去除废水中的ARGs，从而控制其在环境中的扩散和转移具有广阔的前景。

    The widespread of antibiotic resistance genes (ARGs) in the environment can pose severe threats to public health. The wastewater treatment plant (WWTP) is regarded as an important hotspot of ARGs in the urban environment, but the removal of ARGs through conventional treatment techniques has been proven not sufficient. In this study, ferrate (Fe(VI)) was applied for the first time to remove intracellular ARGs from the secondary effluent of the WWTP. The results showed that Fe(VI) treatment could effectively remove 15 ARGs covering eight different types as well as intI1, the most common integron important to ARGs horizontal transfer. The removal efficiencies of tested genes could reach 1.10-4.37 log at the Fe(VI) dosage of 10 mg-Fe/L, which is significantly higher than those achieved through traditional disinfection methods. The DNA gel electrophoresis suggested that Fe(VI) could induce microbial DNA damage and consequently resulted in ARGs elimination. The presence of ARGs in settled residues indicated that coagulation initiated by Fe(VI) reduction products also contributed to ARGs removal from wastewater. In addition, the viability and relative abundances of potential ARGs hosts in the wastewater were decreased after Fe(VI) treatment. This study suggested a promising prospect for applying Fe(VI) to efficiently remove ARGs from wastewater, and consequently to control their proliferation and transfer in the environment.

    https://www.sciencedirect.com/science/article/abs/pii/S0043135420308101