Detection and Molecular Epidemiological Analysis of ESBLs-Producing Escherichia coli Isolated from the Gastrointestinal Tract of Aquatic Organisms

• Published in: Japanese Journal of Infection Prevention and Control Vol. 40; no. 1; pp. 1 - 7
• Main Authors: NAKAJIMA, Masaki, SASAKI, Junpei, MATSUMURA, Mitsuru
• Format: Journal Article
• Language: English; Japanese
• Published: Japanese Society for Infection Prevention and Control 25.01.2025
• Subjects: aquatic organisms; E. coli; ESBLs (blaCTX-M); phylogenetic group typing; POT method
• ISSN: 1882-532X; 1883-2407
• DOI: 10.4058/jsei.40.1

In recent years, the concept of one-health approach has been emphasized, and the spread of drug-resistant bacteria from animals and the environment has become an issue.Escherichia coli producing extended-spectrum β-lactamases (ESBLs), blaCTX-M-15-producing B2-O25-ST131, a global high-risk-clone strain, has been reported in various species.Herein, 20 ESBLs-producing E. coli strains were isolated from gut contents of aquatic environmental organisms, which are rarely studied as target organisms, for resistance gene and molecular epidemiological analyses.All 20 strains tested were classified as phylogenetic group D and harbored blaCTX-M. A total of 13 (65%) strains were blaCTX-M-15, followed by 6 (30%) blaCTX-M-14 and 1 (5%) blaCTX-M-161.Molecular epidemiological analysis using the POT method identified 13 strains harboring blaCTX-M-15, which are the two clonal types D-0166-nonST131 and D-08-nonST131.ESBLs-producing E. coli may have originated from environmental organisms different from the high-risk clone strains frequently detected worldwide.From the one-health approach viewpoint, the trend of such resistant bacteria must be observed from environmental organisms and clinical perspectives.