OXA-23-producing Acinetobacter baumannii: a new hotspot of diversity in Rio de Janeiro?

J Antimicrob Chemother. 2011 Jan;66(1):62-5. doi: 10.1093/jac/dkq406. Epub 2010 Nov 3.


Objectives: this study focused on the population structure of OXA-23-producing Acinetobacter baumannii clinical isolates from Rio de Janeiro, Brazil.

Methods: the analysis included several genomic typing methods, including PFGE, two multilocus sequence typing (MLST) schemes, sequence group (SG) determination and bla(OXA-51-like) sequencing. The genomic context of the bla(OXA-23) gene was also evaluated using I-CeuI hybridizations and PCR assays.

Results: congruent clustering was obtained revealing four lineages. In accordance, four new sequence types (STs) (ST131, ST132, ST133 and ST134) were obtained with the MLST-OD scheme (associated with the Oxford Database) and four (ST79, ST15 and two new allelic profiles) with the MLST-IP scheme (developed by the Institute Pasteur). Four SGs (SG1, SG4 and two new profiles) were identified, allowing the association of 70% of the isolates with European clone II. bla(OXA-51-like) sequencing revealed the presence of bla(OXA-66), bla(OXA-69), bla(OXA-95) and bla(OXA-132).

Conclusions: identification of new STs together with new SG profiles are findings suggestive of a local diversity hotspot that is worth exploring.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acinetobacter Infections / epidemiology*
  • Acinetobacter Infections / microbiology*
  • Acinetobacter baumannii / classification*
  • Acinetobacter baumannii / enzymology*
  • Acinetobacter baumannii / genetics
  • Acinetobacter baumannii / isolation & purification
  • Bacterial Typing Techniques
  • Brazil / epidemiology
  • Cluster Analysis
  • Electrophoresis, Gel, Pulsed-Field
  • Genetic Variation*
  • Genotype
  • Humans
  • Molecular Epidemiology
  • Molecular Typing
  • Nucleic Acid Hybridization
  • Polymerase Chain Reaction
  • Sequence Analysis, DNA
  • beta-Lactamases / biosynthesis*
  • beta-Lactamases / genetics*


  • beta-lactamase OXA-23
  • beta-Lactamases