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bioRxiv · 10.1101/2025.03.27.645688

Identification of plasmid-mediated tigecycline resistance tet(x4) and New Delhi Metallo-β-lactamase (NDM) in an Escherichia coli isolate from Canada

Mataseje, L.·Lerminiaux, N.·McGeer, A.·Johnstone, J.·Poutanen, S.·McGill, E.·Longtin, Y.
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Abstract

SynopsisRapid spread of carbapenemase producing Enterobacterales is a global health threat for which Tigecycline is one of the few remaining therapeutic options. Resistance by tet(x4) is particularly worrisome given its presence on mobile genetic elements. Here we report on a tigecycline-resistant E.coli strain isolated from a patient returning from Pakistan. A tet(x4) gene was found on an IncFII plasmid isolated from an ST410 E.coli co-harbouring NDM-5. The combination of carbapenemase and tet(x4) is concerning.

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Mataseje, L., Lerminiaux, N., McGeer, A., Johnstone, J., Poutanen, S., McGill, E., Longtin, Y.. 2025-03-30. Identification of plasmid-mediated tigecycline resistance tet(x4) and New Delhi Metallo-β-lactamase (NDM) in an Escherichia coli isolate from Canada. https://doi.org/10.1101/2025.03.27.645688

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