The cassettes and 3' conserved segment of an integron from Klebsiella oxytoca plasmid pACM1

Plasmid. 1999 Sep;42(2):104-14. doi: 10.1006/plas.1999.1418.


pACM1 is a conjugative multiresistance plasmid from Klebsiella oxytoca that encodes SHV-5 extended-spectrum beta-lactamase (ESBL) and has two integrons. The first is a type I (sul type); the second, detected by hybridization with an intI gene probe, has been putatively identified as a defective type I integron. The cassette region of the first integron has now been fully sequenced and contains three aminoglycoside resistance determinants (aac(6')-Ib, aac(3)-Ia, and ant(3")-Ia) and two open reading frames of unknown function. In addition, sequencing of a region downstream from the qacEDelta1-sulI-ORF 5 gene cluster of the first integron revealed a copy of insertion sequence IS6100 flanked by inverted copies of sequence from the 11.2-kb insert (In2) of Tn21. This arrangement is similar to that found in In4 of Tn1696. The coincidence of an ESBL gene and mobile elements on a conjugative plasmid has potential implications for the spread of ESBL-mediated drug resistance, though evidence of bla((SHV-5)) movement mediated by these elements has not been found.

MeSH terms

  • Amino Acid Sequence
  • Base Sequence
  • DNA, Bacterial
  • Humans
  • Klebsiella / genetics*
  • Molecular Sequence Data
  • Plasmids*
  • beta-Lactamases / genetics*


  • DNA, Bacterial
  • beta-lactamase SHV-5
  • beta-Lactamases

Associated data

  • GENBANK/AF107205
  • GENBANK/U90945