The potential linkage between antibiotic resistance genes and microbial functions across soil-plant systems

AimsThe proliferation of antibiotic resistance genes (ARGs) is a growing public health concern worldwide. Several studies have substantiated the significant role played by the plant microbiome in facilitating the transmission of antibiotic resistance, thereby posing a substantial threat to human health. However, the underlying mechanism of the transmission of antibiotic resistance from soil to plants is still largely unexplored.MethodsIn the current study, we selected Sedum alfredii as a model plant to investigate the occurrence and distribution of ARGs across the soil-plant interface.ResultsOur results showed that 20.34% of ARGs were significantly shifted between rhizosphere and bulk soils and were linked to distinct variations in bacterial functions across the soil-plant interface. Specifically, the ARGs enriched in the rhizosphere were significantly correlated to microbial functions of signaling pathways and degradation pathways. Conversely, the ARGs depleted in rhizosphere were significantly correlated to microbial functions of biosynthesis pathways, nutrient cycling, and ABC transport system. Moreover, our investigation involved metagenomic contig assembly, providing compelling evidence that these aforementioned relationships were indeed detected in the assembled bins.ConclusionsThe results of our study revealed a clear association between the distribution of ARGs and changes in bacterial functions attributable to the assemblage of the rhizosphere microbiome at the soil-plant interface. These findings significantly contribute to enhancing our comprehension of the mechanism underlying the transmission of ARGs from bulk soils to rhizosphere soils.