Elsevier

Environment International

Volume 128, July 2019, Pages 399-406
Environment International

Does nano silver promote the selection of antibiotic resistance genes in soil and plant?

https://doi.org/10.1016/j.envint.2019.04.061Get rights and content
Under a Creative Commons license
open access

Highlights

  • AgNPs at a concentration of 100 ppm resulted in no significant changes in the total abundance of ARGs.

  • AgNPs application increased the relative abundance of efflux pumps genes.

  • The nanoparticle effect and ion effect of AgNPs was different on the selection of ARGs.

Abstract

Growing evidences have demonstrated that heavy metal contamination can promote the proliferation of antibiotic resistance genes (ARGs) via co-selection. However, effects of nano-metal-materials on the occurrence and level of ARGs in the soil and plant, have not been fully explored. To gain insights into this impact, we conducted a pot experiment by adding nano‑silver particles (AgNPs) as a stimuli and Ag ion (AgNO3) and tetracycline as a comparison. By using high throughput quantitative PCR, our results indicated that application of AgNPs (~20 nm and ~50 nm) at a concentration of 100 ppm resulted in no significant changes in the abundance of ARGs in either soil or phyllosphere (P > 0.05). Nevertheless, the overall pattern of resistome, especially in soil, was shifted following AgNPs application, with a significance increase in the relative abundance of efflux pumps genes, which is an important mechanism for co-selection of ARGs by heavy metals. By comparison, Ag ion at an equivalent Ag mass of AgNPs markedly increased ARGs abundance and shifted ARGs profile in soil, indicating that free Ag ion had a stronger impact on ARGs than AgNPs. These findings provide new insights in assessing the risks of manufactured nanomaterials accumulated in the environment.

Keywords

Nano-materials
Silver nanoparticles
Antibiotic resistance
Co-selection
Plant microbiome

Cited by (0)