摘要

       抗生素耐药性的广泛传播是普遍存在的全球健康威胁，垃圾渗滤液一直是抗生素耐药基因（ARG）的重要热点。本研究旨在研究在不同水力载荷下从渗滤液中去除 ARGs 的性能和机理。 ARGs 去除效率取决于水力负荷和 ARGs 类型而不是运行时间，在 25 和 50L·m-3·d-1 水力负荷下运行的反应堆表现出比 100L·m-3·d-1 更大的去除潜力. ARGs 去除模式因不同亚型而异，因为基因 sul2、tetQ、aadA1 和 blaCTX-M 从渗滤液和垃圾中被消除，tetM、ermB、mefA 和 strB 从渗滤液中去除但富含垃圾。在不同的水力负荷下，细菌群落改变了渗滤液中 ARGs 的命运，但垃圾具有更稳定的抗生素抗性组和群落结构。共生网络的拓扑比较分析表明垃圾中ARGs和属之间的寄主关系比渗滤液更密切。此外，除宿主属多样性外，宿主细菌的分类类别决定了 ARGs 的去除，蓝藻门、Tenericutes 和 Acidobacteria 中含有的 ARGs 更有可能被去除。这些发现有可能促进对不同操作条件下生物处理过程中 ARGs 去除机制的理解。

       The wide dissemination of antibiotic resistance is a pervasive global health threat, and landfill leachate has been an important hotspot of antibiotic resistance genes (ARGs). This study aimed to investigate the removal performance and mechanism of ARGs from leachate under different hydraulic loadings. ARGs removal efficiencies were dependent on hydraulic loadings and ARGs types other than operating time, and reactors operated with hydraulic loadings of 25 and 50 L·m−3·d−1 exhibited greater removal potential than 100 L·m−3·d−1. ARGs removal patterns varied from different subtypes, for genes sul2, tetQ, aadA1 and blaCTX-M were eliminated from both leachate and refuse, and tetM, ermB, mefA, and strB were removed from leachate but enriched in refuse. Under different hydraulic loadings, bacterial communities shift shaped ARGs fates in leachate, but refuse had more stable antibiotic resistome and community structure. The topology comparison analysis of co-occurrence network suggested a closer hosting relationship between ARGs and genera in refuse than leachate. Furthermore, taxonomic category of host bacteria other than diversity of host genera determined the ARGs removal, and the ARGs harbored in phyla Cyanobacteria, Tenericutes and Acidobacteria were more likely to be removed. These findings can potentially foster the understanding of ARGs removal mechanism in biological treatment processes under different operating conditions.

https://www.sciencedirect.com/science/article/abs/pii/S0048969718333321