Comparative genomic analysis of ESBL-selected and non-selected Escherichia coli in Australian wastewater: Elucidating differences in diversity, antimicrobial resistance, and virulence profiles

作者：Veronica M. Jarocki, Dmitriy Li, Daniel R. Bogema, Jerald Yam, Cheryl Jenkins, Faisal I. Hai, Steven P. Djordjevic · 发表于：The Science of The Total Environment · 年份：2024 · DOI：10.1016/j.scitotenv.2024.175079 · 被引用次数：15 · 研究领域：Antibiotic Resistance in Bacteria、Pharmaceutical and Antibiotic Environmental Impacts、Bacterial Identification and Susceptibility Testing

Extended-spectrum β-lactamases (ESBLs)-producing E. coli have been proposed as an indicator bacterium for antimicrobial resistance (AMR) surveillance within a OneHealth framework. However, it is important to understand the effects and potential biases ESBL-selection has on E. coli populations. Utilising whole genome sequencing, this study compared 80 ESBL-selected E. coli isolates with 201 non-selected isolates from Australian wastewater. The findings revealed significant variations between these cohorts in genetic diversity, AMR profiles, and carriage of virulence-associated genes (VAGs), plasmids, and the transmissible Locus of Stress Tolerance (tLST), a genomic island that imparts resistance to extreme heat and chlorination. The study highlights the predominance of certain sequence types (STs), particularly ST131 (75 % clade A), in ESBL-selected isolates (40 % vs 2 %) and overall the ESBL-selected isolates were largely multidrug-resistant (MDR), predominantly carrying genes for resistance to aminoglycosides, extended-spectrum β-lactams, fluoroquinolone, macrolides, sulphonamides/trimethoprim, and tetracyclines. The ESBLs identified were almost exclusively blaCTX-M genes, most commonly blaCTX-M-15 > blaCTX-M-27 > blaCTX-M-14. These were predominately carried on IncF plasmids or chromosomally (always ISEcp1 associated), in equal numbers. In contrast, 80 % of non-selected isolates carried no acquired ARGs, and none carried blaCTX-M genes. In both cohorts, extraintestinal path...