title: Acinetobacter radioresistens as a silent source of carbapenem resistance for Acinetobacter spp.
abstract: Carbapenem resistance results mostly from the expression of acquired carbapenem-hydrolyzing oxacillinases in Acinetobacter baumannii. The bla OXA-23 oxacillinase gene is increasingly reported worldwide and may represent an emerging threat. Our goal was to identify the progenitor of that carbapenemase gene. A collection of 50 Acinetobacter sp. strains corresponding to several Acinetobacter species was screened for bla(OXA-23)-like genes by PCR and hybridization techniques. Five Acinetobacter radioresistens isolates that were susceptible to carbapenems harbored chromosomally encoded bla OXA-23-like genes. A similar plasmid backbone was identified in several bla OXA-23-positive A. baumannii and A. radioresistens isolates, further strengthening the vectors of exchanges for these bla OXA-23-like genes. Therefore, A. radioresistens, a commensal bacterial species which is identified on the skin of hospitalized and healthy patients (a property shared with A. baumannii), was identified as the source of the bla OXA-23 gene.
authors.affiliation: Service de Bactériologie-Virologie, INSERM U914, Emerging Resistance to Antibiotics, Hôpital de Bicêtre, Assistance Publique/Hôpitaux de Paris, Université Paris XI, Le Kremlin-Bicêtre, France.
authors.forename: Laurent
authors.initials: L
authors.lastname: Poirel
authors.forename: Samy
authors.initials: S
authors.lastname: Figueiredo
authors.forename: Vincent
authors.initials: V
authors.lastname: Cattoir
authors.forename: Alessandra
authors.initials: A
authors.lastname: Carattoli
authors.forename: Patrice
authors.initials: P
authors.lastname: Nordmann
mesh_terms: D000150:Acinetobacter / Q000145:classification* / Q000187:drug effects* / Q000201:enzymology / Q000235:genetics; D000595:Amino Acid Sequence; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics; D015780:Carbapenems / Q000494:pharmacology*; D003470:Culture Media; D006801:Humans; D008826:Microbial Sensitivity Tests; D008969:Molecular Sequence Data; D009693:Nucleic Acid Hybridization; D010957:Plasmids; D016133:Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D012867:Skin / Q000382:microbiology; D018440:beta-Lactam Resistance / Q000235:genetics; D001618:beta-Lactamases / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D015780:Carbapenems; D003470:Culture Media; D001618:beta-Lactamases; C108449:oxacillinase