title: Detection of linezolid resistance due to the optrA gene in Enterococcus faecalis from poultry meat from the American continent (Colombia).
abstract: Three Enterococcus isolates obtained from retail chicken collected in 2010-11 as part of the Colombian Integrated Program for Antimicrobial Resistance Surveillance (COIPARS) showed reduced susceptibility towards linezolid (MIC 8 mg/L).
  
  
  
  This study aimed at characterizing the isolates resistant to linezolid and detecting the resistance mechanism.
  
  
  
  Strains were analysed in 2011-12 without successful detection of the resistance mechanism. All isolates were found negative for the cfr gene and no 23S rRNA mutations were detected. In 2016, with the novel resistance gene optrA being described, the WGS data were re-analysed using in silico genomic tools for confirmation of species, detection of virulence and resistance genes, MLST and SNP analyses and comparison of the genetic environment with the previously published plasmid pE349.
  
  
  
  : Three Enterococcus faecalis isolates were found positive for the optrA gene encoding resistance to linezolid and phenicols. Additional screening of 37 enterococci strains from the same study did not detect any further positives. Typing showed that two of the isolates belong to ST59, while the last belongs to ST489. All isolates carry genes encoding resistance to macrolide-lincosamide-streptogramin B, tetracycline and phenicols. In addition, the ST489 isolate also carries genes conferring aminoglycoside resistance and is resistant to quinolones, but no plasmid-mediated gene was detected. The optrA gene regions of the three plasmids showed high similarity to the originally reported optrA -carrying plasmid pE349.
  
  
  
  To the best of our knowledge, this is the first description of the optrA gene in E. faecalis isolated from poultry meat in the Americas.
authors.affiliation: Technical University of Denmark, National Food Institute, WHO Collaborating Center for Antimicrobial Resistance, Kgs Lyngby, Denmark.
authors.forename: L M
authors.initials: LM
authors.lastname: Cavaco
authors.affiliation: Corporación Colombiana de Investigación Agropecuária (CORPOICA), Food Safety, CI Tibaitata, Cundinamarca, Colombia.|Colombian Integrated Program for Antimicrobial Resistance Surveillance (COIPARS), CORPOICA CI Tibaitata, Cundinamarca, Colombia.
authors.forename: J F
authors.initials: JF
authors.lastname: Bernal
authors.affiliation: Technical University of Denmark, National Food Institute, WHO Collaborating Center for Antimicrobial Resistance, Kgs Lyngby, Denmark.
authors.forename: E
authors.initials: E
authors.lastname: Zankari
authors.affiliation: Corporación Colombiana de Investigación Agropecuária (CORPOICA), Food Safety, CI Tibaitata, Cundinamarca, Colombia.|Colombian Integrated Program for Antimicrobial Resistance Surveillance (COIPARS), CORPOICA CI Tibaitata, Cundinamarca, Colombia.
authors.forename: M
authors.initials: M
authors.lastname: Léon
authors.affiliation: Technical University of Denmark, National Food Institute, WHO Collaborating Center for Antimicrobial Resistance, Kgs Lyngby, Denmark.
authors.forename: R S
authors.initials: RS
authors.lastname: Hendriksen
authors.affiliation: Pan American Health Organization, Regional Office for the Americas of the World Health Organization (PAHO), Washington, DC, USA.
authors.forename: E
authors.initials: E
authors.lastname: Perez-Gutierrez
authors.affiliation: Technical University of Denmark, National Food Institute, WHO Collaborating Center for Antimicrobial Resistance, Kgs Lyngby, Denmark.
authors.forename: F M
authors.initials: FM
authors.lastname: Aarestrup
authors.affiliation: Corporación Colombiana de Investigación Agropecuária (CORPOICA), Food Safety, CI Tibaitata, Cundinamarca, Colombia.|Colombian Integrated Program for Antimicrobial Resistance Surveillance (COIPARS), CORPOICA CI Tibaitata, Cundinamarca, Colombia.
authors.forename: P
authors.initials: P
authors.lastname: Donado-Godoy
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D003105:Colombia; D024881:Drug Resistance, Bacterial / Q000235:genetics*; D013293:Enterococcus faecalis / Q000145:classification / Q000187:drug effects* / Q000235:genetics* / Q000302:isolation & purification; D016984:Enterococcus faecium / Q000187:drug effects; D005798:Genes, Bacterial; D000069349:Linezolid / Q000494:pharmacology*; D008826:Microbial Sensitivity Tests; D058885:Multilocus Sequence Typing; D010957:Plasmids; D011200:Poultry / Q000382:microbiology*
chemical_list: D000900:Anti-Bacterial Agents; D000069349:Linezolid