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ORIGINAL RESEARCH article
Front. Microbiol.
Sec. Antimicrobials, Resistance and Chemotherapy
Volume 16 - 2025 |
doi: 10.3389/fmicb.2025.1527546
This article is part of the Research Topic Global Dissemination and Evolution of Epidemic Multidrug-Resistant Gram-Negative Bacterial Pathogens: Surveillance, Diagnosis and Treatment, Volume III View all 13 articles
Genomic analysis of multidrug-resistant Escherichia coli isolated from dairy cows in Shihezi city, Xinjiang, China
Provisionally accepted- Shihezi University, Shihezi, China
Dairy farming is vital to agriculture and nutrition, and the emergence of drug-resistant bacterial strains poses significant risks to public health and animal welfare. Here, we investigated antimicrobial resistance (AMR) and analyzed the genomes of multidrug-resistant (MDR) Escherichia coli isolated from dairy cows in Shihezi City, Xinjiang, China. We isolated E. coli strains from dairy cow feces and tested their resistance to 14 antibiotics using the Kirby-Bauer disk diffusion method. We also sequenced the genomes of two MDR isolates (E.coli_30 and E.coli_45) and conducted a comprehensive genomic analysis. Results of the drug test revealed that 22.9% of isolates exhibited MDR, particularly to antibiotics such as imipenem and ciprofloxacin, while gentamicin and tetracycline were the most effective. Comprehensive Antibiotic Resistance Database (CARD) identified key AMR genes, including mphA, qnrS1, and blaCTX-M-55 (only in E.coli_45), which confer resistance to macrolides, quinolones, and beta-lactams, respectively. We also identified virulence factors, such as genes encoding TTSS and adhesion factors, which contribute to the pathogenic potential of these strains. Phylogenetic analysis revealed distinct evolutionary lineages for the two isolates. This suggests that they originated from different ancestral populations. The presence of two extended-spectrum ꞵ-lactamase (ESBL) genes in E.coli_45 was noticeable, so we studied their evolutionary distribution across the world and within China. We found that they are endemic in E.coli, Salmonella enterica, and Klebsiella pneumoniae. A pangenome analysis of 50 E. coli strains with diverse sequence types revealed significant genetic diversity, with unique strain-specific genes related to metabolism and stress response, indicating the bacteria's adaptation to various environments. The identification of mobile genetic elements (MGEs), including insertion sequences (IS) and transposons, highlighted their role in the bacterial adaptation and diversity. The result of this study highlights the growing threat of AMR in dairy farms and emphasize the importance of monitoring and mitigating the spread of MDR bacteria to protect both animal and public health.
Keywords: E. coli, AMR, MDR, ESBL, MGE, Genomes
Received: 13 Nov 2024; Accepted: 06 Feb 2025.
Copyright: © 2025 Bello, Ning, Zhang, Ni and Shengwei. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
* Correspondence:
Siqi Ning, Shihezi University, Shihezi, China
Wei Ni, Shihezi University, Shihezi, China
Hu Shengwei, Shihezi University, Shihezi, China
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