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PubMed · 42678601

Genomic insights into an optrA-carrying plasmid associated with linezolid resistance in clinical Enterococcus faecalis isolates, Argentina.

Celia Marìa Schell·Gloria Magi·Serena Simoni·Francesca Romana Massacci·Elisa Albini·Gloria D'Achille·Claudia Paoletti·Filomena Carriera·Gianluca Morroni·Marina Mingoia·Yao Zhu·Wanjiang Zhang·Xiang-Dang Du·Henrike Krüger-Haker·Stefan Schwarz·Judith Celina Bernstein·Eleonora Giovanetti·Andrea Brenciani
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Abstract

The spread of the transferable optrA gene poses an increasing threat to the clinical efficacy of oxazolidinones. Here, we characterized a novel optrA-carrying plasmid, pEfa-optrA-Arg, from a linezolid-resistant Enterococcus faecalis clinical isolate from Argentina. The 68,653-bp conjugative plasmid harbored optrA together with multiple antimicrobial resistance genes and showed high similarity to a plasmid previously identified in a bovine isolate from Switzerland. pEfa-optrA-Arg, or a closely related variant, was also detected in E. faecalis isolates from several Argentinian hospitals, highlighting the role of horizontal gene transfer in the spread of antimicrobial resistance across human and animal reservoirs within the One Health continuum.

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Enterococcus faecalisoptrAConjugative plasmidsOxazolidinone resistanceST314Journal Article

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Celia Marìa Schell, Gloria Magi, Serena Simoni, Francesca Romana Massacci, Elisa Albini, Gloria D'Achille, Claudia Paoletti, Filomena Carriera, Gianluca Morroni, Marina Mingoia, Yao Zhu, Wanjiang Zhang, Xiang-Dang Du, Henrike Krüger-Haker, Stefan Schwarz, Judith Celina Bernstein, Eleonora Giovanetti, Andrea Brenciani. 2026-09-01. Genomic insights into an optrA-carrying plasmid associated with linezolid resistance in clinical Enterococcus faecalis isolates, Argentina.. https://doi.org/10.1007/s10096-026-05657-4

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