摘要

       采用高通量测序的宏基因组分析和网络分析方法，研究了中国12个城市垃圾渗滤液中ARGs的广谱分布。共检测到526个ARG亚型，隶属于21个ARG亚型，其含量范围为ARG/16srrna基因拷贝数的1.1~2.09~10-1个。共有68个ARG亚型，占总ARG丰度的73.4%-93.4%。四个最丰富的ARG，sul1，sul2，aadA和bacA可以作为ARG指标，用线性函数（r2 = 0.577-0.819，P <0.001）定量预测总丰度。我国不同城市间的ARGs没有明显的区域分布格局，而渗滤液的ARG组成与其他环境样品类型有明显的差异。污水处理厂（STPADS）厌氧消化污泥中近90%的ARG亚型被渗滤液所共有，渗滤液和STPADS-ARGs的总丰度分别占这两类厌氧样品总丰度的84.5%和87.7%。Procrustes分析表明，微生物群落组成可能是垃圾渗滤液中ARG组成的决定因素。同一类型或不同类型间的ARGs表现出较高的非随机共生率，17属可能是多个ARGs的潜在寄主。研究表明，垃圾渗滤液是各种ARGs的重要储集层，为填埋环境中ARGs的监测和风险管理提供了有益的参考。

        High throughput sequencing-based metagenomic analysis and network analysis were applied to investigate the broad-spectrum profiles of ARGs in landfill leachate from 12 cities in China. In total, 526 ARG subtypes belonging to 21 ARG types were detected with abundances ranging from 1.1 × 10^-6 to 2.09 × 10^-1 copy of ARG/copy of 16S rRNA gene. 68 ARG subtypes that accounted for 73.4%-93.4% of the total ARG abundances were shared by all leachate samples. The four most abundant ARGs, sul1, sul2, aadA and bacA can be served as ARG indicators to quantitatively predict the total abundances by linear functions (r² = 0.577-0.819, P < 0.001). No distinct regional distribution pattern of the ARGs was observed among different cities in China, while the ARG compositions of the leachate were clearly distinct from those of other environmental sample types. Nearly 90% ARG subtypes in the anaerobic digestion sludge from sewage treatment plants (STPADS) were shared by the leachate and the abundances of leachate and STPADS ARGs generalists accounted for 84.5% and 87.7% of total abundances in these two types of anaerobic samples, respectively. Furthermore, Procrustes analysis suggested that microbial community composition might be the determining factor of ARG compositions in landfill leachate. ARGs within the same type or among the different types showed higher incidences of non-random co-occurrence and 17 genera might be potential hosts of multiple ARGs. This study highlighted that landfill leachate is an important reservoir of various ARGs and provided a useful reference for the surveillance and risk management of ARGs in landfill environments.

        https://www.sciencedirect.com/science/article/abs/pii/S0043135418300836?via%3Dihub