摘要

现代环境中抗生素抗性基因（ARGs）的流行引发了一个新兴的全球健康问题。在这项研究中，土壤样本从石化厂的三个地点采集，代表不同污染水平的多环芳烃（PAHs）。这些土壤的宏基因组分析表明，PAHs污染土壤中的ARGs比污染程度较低土壤中的ARGs大约多15倍，其中Proteobacterial是优势门。 ARGs在PAHs污染土壤中的耐药性特征表现为与芳香族抗生素（例如氟喹诺酮和吖啶黄）相关的外排泵编码ARGs的占优势，占总ARGs的70％以上，这与代表性显着不同广泛使用抗生素导致的ARG污染源。富含PAHs污染土壤中的大多数ARG不被质粒携带，表明它们在细菌之间转移的可能性很低。 ARGs的总丰度与土壤中Proteobacteria的总丰度之间存在显着相关性。被PAHs选择的变形杆菌导致它们在土壤中携带的ARGs同时富集。我们的研究结果表明，PAHs可以作为ARGs在人类受影响环境中大量富集的选择性压力之一。

The prevalence of antibiotic resistance genes (ARGs) in modern environment raises an emerging global health concern. In this study, soil samples were collected from three sites in petrochemical plant that represented different pollution levels of polycyclic aromatic hydrocarbons (PAHs). Metagenomic profiling of these soils demonstrated that ARGs in the PAHs-contaminated soils were approximately 15 times more abundant than those in the less-contaminated ones, with Proteobacterial being the preponderant phylum. Resistance profile of ARGs in the PAHs-polluted soils was characterized by the dominance of efflux pump-encoding ARGs associated with aromatic antibiotics (e.g., fluoroquinolones and acriflavine) that accounted for more than 70% of the total ARGs, which was significantly different from representative sources of ARG pollution due to wide use of antibiotics. Most of ARGs enriched in the PAHs-contaminated soils were not carried by plasmids, indicating the low possibilities of them being transferred between bacteria. Significant correlation was observed between the total abundance of ARGs and that of Proteobacteria in the soils. Proteobacteria selected by PAHs led to simultaneously enriching of ARGs carried by them in the soils. Our results suggested that PAHs could serve as one of selective stresses for greatly enriching of ARGs in the human-impacted environment.

https://www.sciencedirect.com/science/article/pii/S026974911631137X