Impact of urbanization on antimicrobial resistance in soil microbial communities

Soil is one of the most important reservoirs of antibiotic resistance, global threat that needs to be addressed with the One Health approach. Despite urban parks playing a fundamental role in urban ecosystems, the diffusion, maintenance, and human impact of antibiotic-resistance genes in this substrate are still poorly addressed. To fill in this gap, we adopted a molecular and culturomics approach to study antibiotic resistance in urban parks, accounting for the environmental matrix and the level of urbanization. A higher abundance of efflux-mediated mechanisms in undisturbed environments was observed, while antibiotic alteration or inactivation, and target replacement were more abundant in areas with a higher level of urbanization, also confirmed by significant correlations with anthropogenic features of the environmental matrix. Overall, this study highlights the crucial need to monitor antibiotic resistance in urban parks' soil through a dual molecular and culturomics approach to fully understand and fight antibiotic resistance diffusion.