摘要

       抗生素的大量使用导致其不断释放到环境中，随后抗生素耐药菌（ARB）、抗生素耐药基因（ARGs）和移动基因元件（MGEs）的广泛出现。本研究采用Illumina高通量测序法，研究了某污水处理厂活性污泥和厌氧消化污泥中ARGs和MGEs的广谱分布。建立了一条鉴定抗生素耐药决定因素的管道，该管道由基因转移潜能、ARG潜能、ARGs途径和ARGs系统发育起源四类组成。宏基因组分析表明，活性污泥和消化污泥中的微生物群落不同，ARGs和MGEs的种类和发生率也不同。活性污泥中共鉴定出42种ARGs亚型，消化污泥中检测到51种ARG亚型。此外，两种污泥样品中均含有大量的MGEs，包括质粒、转座子、整合子（intI1）和插入序列（如ISSsp4、ISMsa21和ISMba16）。通过网络分析揭示了ARGs与微生物类群的共生模式，表明一些环境细菌（如梭菌和亚硝基单胞菌）可能是多种ARGs的潜在宿主。这些发现增加了我们对作为ARGs和MGEs热点的污水处理厂的认识，并有助于防止它们释放到下游环境中。

       The intensive use of antibiotics results in their continuous release into the environment and the subsequent widespread occurrence of antibiotic resistant bacteria (ARB), antibiotic resistance genes (ARGs) and mobile genetic elements (MGEs). This study used Illumina high-throughput sequencing to investigate the broad-spectrum profiles of both ARGs and MGEs in activated sludge and anaerobically digested sludge from a full-scale wastewater treatment plant. A pipeline for identifying antibiotic resistance determinants was developed that consisted of four categories: gene transfer potential, ARG potential, ARGs pathway and ARGs phylogenetic origin. The metagenomic analysis showed that the activated sludge and the digested sludge exhibited different microbial communities and changes in the types and occurrence of ARGs and MGEs. In total, 42 ARGs subtypes were identified in the activated sludge, while 51 ARG subtypes were detected in the digested sludge. Additionally, MGEs including plasmids, transposons, integrons (intI1) and insertion sequences (e.g. ISSsp4, ISMsa21 and ISMba16) were abundant in the two sludge samples. The co-occurrence pattern between ARGs and microbial taxa revealed by network analysis indicated that some environmental bacteria (e.g. Clostridium and Nitrosomonas) might be potential hosts of multiple ARGs. The findings increase our understanding of WWTPs as hotspots of ARGs and MGEs, and contribute towards preventing their release into the downstream environment.

        https://www.sciencedirect.com/science/article/abs/pii/S0043135417305651?via%3Dihub