摘要

    垃圾填埋场是环境中出现抗生素抗性基因（ARG）的热点。但是，由于垃圾掩埋场中垃圾的年龄不同，因此关于ARGs概况的信息不多。在这项研究中，通过高通量定量PCR评估了中国垃圾填埋场中ARG的多样性，丰度和表达。总共检测到154个ARG，其中66％具有转录活性。 ARG转录本的总丰度比ARGs低1个数量级。发现ermT-01，tetX，sul2，aadA-02和aadA2-33基因是最丰富的ARG（ARG转录本），它们的总和与ARGs（ARG转录本）的总丰富度呈线性关系。主坐标分析显示，年轻垃圾中ARGs（ARG转录本）的总丰度显着高于老垃圾中（p <0.01），而老龄和年轻垃圾之间的ARGs（ARG转录本）的轮廓很明显。变异分区分析表明，重金属（主要是Cr和Zn）是影响ARGs（ARG转录本）分布的主要驱动因素。这些发现为垃圾填埋场的ARG提供了新的见解，并表明了它们的潜在威胁不容忽视。

    Landfills are the hotspots for the occurrence of antibiotic resistance genes (ARGs) in the environment. However, limited information is available on the profile of ARGs in response to the varying age of refuse in landfills. In this study, the diversity, abundance and expression of ARGs in a Chinese landfill were assessed by high-throughput quantitative PCR. A total of 154 ARGs were detected and 66% of them were transcriptionally active. The total abundance of ARG transcripts was one magnitude lower than that of ARGs. The ermT-01, tetX, sul2, aadA-02 and aadA2–03 genes were found to be the most abundant ARGs (ARG transcripts) and their sum abundance showed a linear relation with the total abundance of ARGs (ARG transcripts). The total abundance of ARGs (ARG transcripts) in young refuse was significantly higher than that in old refuse (p < 0.01) and the profile of ARGs (ARG transcripts) between the old and young refuse was distinct as revealed by the principal coordinates analysis. The variation partitioning analysis showed heavy metals (mainly Cr and Zn) were the major drivers that affect the profile of ARGs (ARG transcripts). These findings provided new insights into the ARGs in landfills and indicated their potential threats should not be neglected.

    https://www.sciencedirect.com/science/article/abs/pii/S0304389421009912