Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences , 1799 Jimei Road , Xiamen 361021 , China.
University of Chinese Academy of Sciences , 19A Yuquan Road , Beijing 100049 , China.
Environ Sci Technol. 2019 Jul 2;53(13):7770-7781. doi: 10.1021/acs.est.9b00214. Epub 2019 Jun 18.
The presence and spread of antibiotic resistance genes (ARGs) are causing substantial global public concern; however, the dispersal of ARGs in the food chain is poorly understood. Here, we experimented with a soil collembolan ( Folsomia candida)-predatory mite ( Hypoaspis aculeifer) model food chain to study trophic transfer of ARGs in a manure-contaminated soil ecosystem. Our results showed that manure amendment of soil could significantly increase ARGs in the soil collembolan microbiome. With the ARGs in the prey collembolan microbiome increasing, an increase in ARGs in the predatory mite microbiome was also observed, especially for three high abundant ARGs ( blaSHV, fosX and aph6ia). Three unique ARGs were transferred into the microbiome of the predatory mite from manure amended soil via the prey collembolan ( aac(6' )-lb(akaaacA4), yidY_mdtL and tolC). Manure amendment altered the composition and structure and reduced the diversity of the microbiomes of the prey collembolan and the predatory mite. We further reveal that bacterial communities and mobile genetic elements were two important drivers for the trophic transfer of ARGs, not just for ARGs distribution in the samples. These findings suggest that the importance of food chain transmission of ARGs for the dispersal of resistance genes in soil ecosystems may be underestimated.
抗生素耐药基因（ARGs）的存在和传播引起了全球公众的极大关注；然而，食物链中 ARGs 的传播仍知之甚少。在这里，我们通过土壤弹尾目动物（ Folsomia candida）-捕食螨（ Hypoaspis aculeifer）模型食物链进行实验，研究了受粪便污染的土壤生态系统中 ARGs 的营养转移。我们的结果表明，土壤添加粪便可以显著增加土壤弹尾目微生物群落中的 ARGs。随着猎物弹尾目微生物群落中 ARGs 的增加，捕食螨微生物群落中的 ARGs 也增加了，特别是三种高丰度的 ARGs（blaSHV、fosX 和 aph6ia）。通过猎物弹尾目，三种独特的 ARGs（aac(6')-lb(akaaacA4)、yidY_mdtL 和 tolC）从添加粪便的土壤中转移到捕食螨的微生物群落中。粪便添加改变了猎物弹尾目和捕食螨微生物群落的组成和结构，降低了它们的多样性。我们进一步揭示，细菌群落和移动遗传元件是 ARGs 营养转移的两个重要驱动因素，而不仅仅是 ARGs 在样品中的分布。这些发现表明，食物链传播 ARGs 对土壤生态系统中抗性基因传播的重要性可能被低估了。
