This study uses genomic analysis to characterize antimicrobial resistance and virulence profiles of extraintestinal pathogenic E. coli (ExPEC) strains isolated from canine urinary tract infections in Brazil, identifying β-lactamase genes and quinolone resistance mutations associated with clinical resistance. It highlights the prevalence of multidrug-resistant (MDR) ExPEC in companion animals and their potential risk for interspecies transmission.
Literature Overview
The paper "Clonal Diversity of Extraintestinal Pathogenic Escherichia coli Strains Isolated from Canine Urinary Tract Infections in Brazil" published in Antibiotics reviews genomic features of four MDR or phylogroup B2 E. coli strains among 60 isolates collected between March and May 2023 from São Paulo, Brazil. It reveals antibiotic resistance genes, virulence factors, and plasmid-mediated horizontal gene transfer potential. The study emphasizes the importance of genomic surveillance of MDR ExPEC in companion animals for human health and ExPEC epidemiology.
Background Knowledge
Extraintestinal pathogenic E. coli (ExPEC) is a significant pathogen causing urinary tract infections (UTIs) in humans and animals, particularly phylogroup B2. Its widespread virulence factors and drug resistance make it a clinical concern. In human medicine, ExPEC correlates with resistant UTIs and bacteremia, while veterinary trends suggest companion animals may serve as reservoirs or vectors for resistant strains. Resistance genes like blaCTX-M-55 and blaCMY-2 are frequently found on mobile genetic elements, enabling horizontal transfer between hosts. Quinolone resistance mutations (e.g., GyrA, ParC) reduce clinical efficacy. Virulence factors include adhesins, iron acquisition systems, immune evasion proteins, and toxins essential for bacterial colonization and persistent infection. Coexistence of plasmid-mediated resistance and virulence genes increases clinical treatment challenges. This study provides genomic insights through whole-genome sequencing and bioinformatics analysis, filling epidemiological gaps in Brazilian companion animals and contributing to global One Health antimicrobial resistance research.
Research Methods and Experiments
The team collected 60 canine E. coli isolates from a São Paulo clinical laboratory (March-May 2023) for antimicrobial susceptibility testing and phylogroup classification. Four strains (6.6%) identified as MDR or phylogroup B2 underwent whole-genome sequencing (WGS). Phylogroups were analyzed using ClermonTyping v23.06, MDR status per Magiorakos criteria. Resistance genes/mutations were annotated via ResFinder v4.7.2, MLST v2.0, CHI-Typer v1.0, SerotypeFinder v2.0. Virulence factors were identified with VirulenceFinder v2.0, plasmid replicons via PlasmidFinder v2.1. Genomic context analysis used ISfinder and BLAST.
Key Conclusions and Perspectives
Research Significance and Prospects
The study reveals genomic similarities between canine and human ExPEC strains, underscoring companion animals' role in the One Health framework. Future work requires expanded sampling across regions and larger cohorts to assess resistance clone dynamics and host adaptation. Plasmid-mediated co-transfer mechanisms need experimental validation to clarify cross-host transmission potential.
Conclusion
This genomic analysis of canine UTI-derived E. coli in Brazil identifies strains carrying blaCTX-M-55, blaCMY-2, quinolone resistance mutations, and multiple virulence genes. The presence of phylogroups B2/G, multidrug-resistant phenotypes, and plasmid-mediated resistance gene spread suggests companion animals act as reservoirs for resistant clones. The study emphasizes cross-sectoral genomic epidemiology applications in veterinary and clinical research, providing foundational data for investigating resistance transmission pathways. Cyagen Biosciences offers comprehensive services from animal model development to pharmacodynamic evaluation, supporting follow-up studies on host adaptation, transmission mechanisms, and therapeutic interventions.
