Molecular characterization of bla(IMP-5), a new integron-borne metallo-beta-lactamase gene from an Acinetobacter baumannii nosocomial isolate in Portugal

FEMS Microbiol Lett. 2002 Sep 24;215(1):33-9. doi: 10.1111/j.1574-6968.2002.tb11366.x.


Acinetobacter baumannii 65FFC, an imipenem-resistant clinical strain, isolated from the urine of a patient at the Coimbra University Hospital, Portugal, in 1998, produced a metallo-beta-lactamase with a calculated pI 9.3. The isolate was highly resistant to penicillins, broad-spectrum cephalosporins, including ceftazidime, ceftriaxone, cefepime, cefpirome, and to aztreonam, but it remained susceptible to ampicillin/sulbactam, aminoglycosides and quinolones. Nucleotide sequence revealed a new allelic variant of other bla(IMP) genes, named bla(IMP-5). IMP-5 beta-lactamase showed a greater homology with IMP-1, IMP-3 and IMP-4 (identified in Southeast Asia), than with IMP-2, found in Italy (93%, 92%, 91% and 87% of amino acid identity, respectively). bla(IMP-5) was the only gene cassette inserted into a class 1 integron, named In76. This is the first IMP-enzyme reported in Portugal and the second in Europe, indicating a wider dissemination in the environment of bla(IMP) alleles.

MeSH terms

  • Acinetobacter Infections / microbiology*
  • Acinetobacter Infections / urine
  • Acinetobacter baumannii / genetics*
  • Amino Acid Sequence
  • Anti-Bacterial Agents
  • Base Sequence
  • Cloning, Molecular
  • Cross Infection / microbiology*
  • Cross Infection / urine
  • Humans
  • Imipenem
  • Integrons / genetics
  • Molecular Sequence Data
  • Portugal
  • beta-Lactam Resistance
  • beta-Lactamases / genetics*


  • Anti-Bacterial Agents
  • Imipenem
  • beta-Lactamases

Associated data

  • GENBANK/AF290912