Effects of Zinc Thiazole and Oxytetracycline on the Microbial Metabolism, Antibiotic Resistance, and Virulence Factor Genes of Soil, Earthworm Gut, and Phyllosphere

Abstract

Pesticides and antibiotics are believed to increase the incidence of antibiotic resistance genes (ARGs) and virulence factor genes (VFGs), constituting a serious threat to global health. However, the impact of this combined pollution on the microbiome and that of the related ARGs and VFGs on soil–plant–animal systems remain unknown. In this study, a 60-day microcosm experiment was conducted to reveal the effects of zinc thiazole (ZT) and oxytetracycline (OTC) on microbial communities, antibiotic resistomes, and virulence factors in soil, earthworm gut, and phyllosphere samples using metagenomics. ZT exposure perturbed microbial communities and nutrient metabolism and increased the abundance of ARGs and VFGs in the gut. Combined exposure changed the profiles of ARGs and VFGs by decreasing microbial diversity in the phyllosphere. Host-tracking analysis identified some genera, such as Citrobacter and Aeromonas, as frequent hosts of ARGs and VFGs in the gut. Notably, some co-occurrence patterns of ARGs and MGEs were observed on the metagenome-assembled contigs. More importantly, ZT markedly increased the abundance of potentially drug-resistant pathogens Acinetobacter soli and Acinetobacter junii in the phyllosphere. Overall, this study expands our current understanding of the spread of ARGs and VFGs in soil–plant–animal systems under pollutant-induced stress and the associated health risks.

Trophic Transfer and Toxic Potency of Rare Earth Elements along a Terrestrial Plant–Herbivore Food Chain

“…These findings demonstrate a dose-dependent effect of trophically transferred REEs on the disruption of intestinal microbiota in the snails. Similarly, other researchers have reported that intestinal microbial flora has a high sensitivity to extraneous chemicals such as metals, pesticides and antibiotics, , and particles. , This effect on the snail gut microbiome was not directly due to the fact that the snails were exposed indirectly to the REEs. Previous studies have shown that REEs directly affected the bacteria in the phyllosphere and leaf of a soil–rice system and changed the metabolites in the leaves of plants .…”