Characterization of CMY-type Beta-Lactamases in Clinical Strains of Proteus Mirabilis and Klebsiella Pneumoniae Isolated in Four Hospitals in the Paris Area

J Antimicrob Chemother. 2002 Nov;50(5):681-8. doi: 10.1093/jac/dkf193.


We isolated five clinical strains (three Proteus mirabilis and two Klebsiella pneumoniae) with beta-lactam resistance phenotypes consistent with production of an AmpC-type beta-lactamase. The predicted amino acid sequences of the enzymes were typical of class C beta-lactamases. The enzymes were identified as CMY-2, CMY-4 and a new CMY-variant beta-lactamase, CMY-12. The AmpC beta-lactamases from the two K. pneumoniae isolates were found to be encoded on self-transferable plasmids. The genes encoding the AmpC-type beta-lactamase produced by the three P. mirabilis isolates were chromosomal. Four of the five clinical isolates were from patients transferred from Greece, Algeria and Egypt; one of the K. pneumoniae strains was recovered from a French patient. PFGE analysis and rep-PCR fingerprinting showed that the two P. mirabilis isolates from Greek patients were closely related.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cross Infection / enzymology*
  • Cross Infection / microbiology*
  • Humans
  • Klebsiella Infections / enzymology
  • Klebsiella Infections / epidemiology
  • Klebsiella Infections / microbiology
  • Klebsiella pneumoniae / enzymology
  • Klebsiella pneumoniae / isolation & purification*
  • Microbial Sensitivity Tests / statistics & numerical data
  • Paris / epidemiology
  • Proteus Infections / enzymology
  • Proteus Infections / epidemiology
  • Proteus Infections / microbiology
  • Proteus mirabilis / enzymology
  • Proteus mirabilis / isolation & purification*
  • beta-Lactamases / chemistry
  • beta-Lactamases / genetics
  • beta-Lactamases / isolation & purification*


  • beta-lactamase CMY-2
  • beta-Lactamases