Conjugative plasmids-associated to shape the antibiotic resistance dissemination prevalence in European urban wastewater systems
Antibiotic resistance (AR) surveillance is a global health priority, and urban wastewater systems are recognized reservoirs for resistance dissemination. Conjugative plasmids play a central role in horizontal gene transfer, yet their phenotypic contributions to resistance spread remain poorly characterized. Here, we investigated conjugative plasmids from hospital and residential influent sewers in three European countries (Denmark, Spain, and the United Kingdom) using exogenous plasmid capture, phenotypic profiling, and genomic sequencing. Among 797 captured plasmids, antimicrobial susceptibility testing revealed that multidrug resistance was widespread, with most plasmids conferring resistance to multiple antibiotic classes. Comparative analysis of plasmidome datasets and captured conjugative plasmids showed that ARG abundance at the community level did not consistently correspond to phenotypic resistance, indicating that transferable plasmids represent a functionally distinct subset of the broader plasmid-associated resistome. Sequencing of 96 representative plasmids further revealed structured associations between resistance genes, incompatibility groups, and mobility types, as well as evidence of modular genome organization in which resistance gene regions are shared across distinct plasmid backbones. Together, these results indicate that plasmid-mediated resistance in wastewater is shaped by host compatibility and plasmid architecture, highlighting the importance of integrating phenotypic and genomic data to better understand the ecological dynamics of antimicrobial resistance
Antibiotic resistance (AR) surveillance is a global health priority, and urban wastewater systems are recognized reservoirs for resistance dissemination. Conjugative plasmids play a central role in horizontal gene transfer, yet their phenotypic contributions to resistance spread remain poorly characterized. Here, we investigated conjugative plasmids from hospital and residential influent sewers in three European countries (Denmark, Spain, and the United Kingdom) using exogenous plasmid capture, phenotypic profiling, and genomic sequencing. Among 797 captured plasmids, antimicrobial susceptibility testing revealed that multidrug resistance was widespread, with most plasmids conferring resistance to multiple antibiotic classes. Comparative analysis of plasmidome datasets and captured conjugative plasmids showed that ARG abundance at the community level did not consistently correspond to phenotypic resistance, indicating that transferable plasmids represent a functionally distinct subset of the broader plasmid-associated resistome. Sequencing of 96 representative plasmids further revealed structured associations between resistance genes, incompatibility groups, and mobility types, as well as evidence of modular genome organization in which resistance gene regions are shared across distinct plasmid backbones. Together, these results indicate that plasmid-mediated resistance in wastewater is shaped by host compatibility and plasmid architecture, highlighting the importance of integrating phenotypic and genomic data to better understand the ecological dynamics of antimicrobial resistance
University of Copenhagen