Dynamics of Enterobacteriaceae reservoirs harboring blaCTX-M group 1 in community wastewater systems
The rising prevalence of clinically significant blaCTX-M group 1 resistance genes in human populations underscores the need for further investigation, particularly to elucidate the establishment and dynamics of environmental reservoirs. In this study, we combined molecular and culture-based approaches to examine the potential origins, abundance, and temporal dynamics of blaCTX-M group 1 genes in wastewater systems. We performed whole-genome sequencing for 24 selectively isolated Escherichia coli strains to assess their antibiotic resistance, particularly the presence of the blaCTX-M gene, and virulence gene profiles. Our results revealed a high prevalence of blaCTX-M group 1 genes among wastewater E. coli, with resistance and virulence profiles closely resembling those observed in clinical isolates, highlighting the importance of monitoring antibiotic resistance in wastewater systems.