title: Snapshot on carbapenemase-producing Pseudomonas aeruginosa and Acinetobacter baumannii in Bucharest hospitals reveals unusual clones and novel genetic surroundings for blaOXA-23.
abstract: OBJECTIVE
  The present study was designed to provide a snapshot on carbapenemase-producing Pseudomonas aeruginosa (n=11) and Acinetobacter baumannii (n=7) isolates in hospitalized patients (November 2011, January-March 2012) from two main hospitals in Bucharest, south Romania.
  
  
  METHODS
  Clonality among isolates was established by PFGE, MLST and Fourier transform infrared spectroscopy. Carbapenemases were screened by the Blue-Carba test, PCR and sequencing. Transferability of blaOXA-23 was tested by conjugation and plasmid typing (number, size and identity) was assessed by S1-PFGE, replicon typing, hybridization and PCR mapping.
  
  
  RESULTS
  All P. aeruginosa isolates carried chromosomally located blaVIM-2, associated with a common class 1 integron (aacA7-blaVIM-2) or an atypical configuration (aacA7-blaVIM-2-dfrB5-tniC). These isolates belonged to unusual lineages; mostly ST233 disseminated in one hospital unit, with ST364 and ST1074 also being detected. A. baumannii isolates carried blaOXA-23 in Tn2008, which was found truncating a TnaphA6 transposon located in a common 60 kb GR6 (aci6) pABKp1-like conjugative plasmid in highly related CC92 clones (ST437, ST764 and ST765), where CC stands for clonal complex.
  
  
  CONCLUSIONS
  Our results show the spread of VIM-2-producing P. aeruginosa and OXA-23-producing A. baumannii clinical isolates in two hospitals from Bucharest and highlight a peculiar population structure in this Eastern European country. Also, we demonstrate the dissemination of a common and conjugative aci6 pABKp1-like plasmid scaffold in different A. baumannii clones and we report the first known identification of Tnaph6-carrying pACICU2-like plasmids in Europe.
authors: Department of Microbiology, Faculty of Biology, University of Bucharest, Bucharest, Romania.
authors: Irina
authors: I
authors: Gheorghe
authors: UCIBIO/REQUIMTE, Laboratório de Microbiologia, Faculdade de Farmácia, Universidade do Porto, Porto, Portugal.
authors: Ângela
authors: Â
authors: Novais
authors: UCIBIO/REQUIMTE, Laboratório de Microbiologia, Faculdade de Farmácia, Universidade do Porto, Porto, Portugal.
authors: Filipa
authors: F
authors: Grosso
authors: UCIBIO/REQUIMTE, Laboratório de Microbiologia, Faculdade de Farmácia, Universidade do Porto, Porto, Portugal.
authors: Carla
authors: C
authors: Rodrigues
authors: Department of Microbiology, Faculty of Biology, University of Bucharest, Bucharest, Romania.
authors: Mariana Carmen
authors: MC
authors: Chifiriuc
authors: Department of Microbiology, Faculty of Biology, University of Bucharest, Bucharest, Romania.
authors: Veronica
authors: V
authors: Lazar
authors: UCIBIO/REQUIMTE, Laboratório de Microbiologia, Faculdade de Farmácia, Universidade do Porto, Porto, Portugal lpeixe@ff.up.pt.
authors: Luísa
authors: L
authors: Peixe
mesh_terms: D000151:Acinetobacter Infections / Q000382:microbiology*; D040981:Acinetobacter baumannii / Q000145:classification / Q000201:enzymology* / Q000235:genetics / Q000302:isolation & purification; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D003227:Conjugation, Genetic; D003428:Cross Infection / Q000382:microbiology*; D016521:Electrophoresis, Gel, Pulsed-Field; D022761:Gene Transfer, Horizontal; D005838:Genotype; D006761:Hospitals; D006801:Humans; D058885:Multilocus Sequence Typing; D009693:Nucleic Acid Hybridization; D010957:Plasmids / Q000032:analysis / Q000145:classification; D016133:Polymerase Chain Reaction; D011552:Pseudomonas Infections / Q000382:microbiology*; D011550:Pseudomonas aeruginosa / Q000145:classification / Q000201:enzymology* / Q000235:genetics / Q000302:isolation & purification; D012383:Romania; D017550:Spectroscopy, Fourier Transform Infrared; D001618:beta-Lactamases / Q000235:genetics / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D001618:beta-Lactamases; C063912:carbapenemase
keywords: OXA-23; ST233; ST437; Tn2008; TnaphA6; VIM-2; pACICU2 plasmid