Gene mutations responsible for overexpression of AmpC beta-lactamase in some clinical isolates of Enterobacter cloacae

J Clin Microbiol. 2005 Jun;43(6):2955-8. doi: 10.1128/JCM.43.6.2955-2958.2005.

Abstract

AmpC regulatory genes in 21 ceftazidime-resistant clinical isolates of Enterobacter cloacae (MICs of > or = 16 microg/ml) were characterized. All isolates exhibited AmpC overproduction due to AmpD mutation. Additionally, we found two AmpR mutants among the isolates. This is the first report of chromosomal ampR mutation in clinical isolates of E. cloacae.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anti-Bacterial Agents / pharmacology
  • Bacterial Proteins / genetics*
  • Bacterial Proteins / metabolism*
  • Ceftazidime / pharmacology
  • Cephalosporin Resistance
  • Enterobacter cloacae / drug effects
  • Enterobacter cloacae / enzymology*
  • Enterobacter cloacae / genetics
  • Enterobacter cloacae / isolation & purification
  • Enterobacteriaceae Infections / microbiology
  • Gene Expression Regulation, Bacterial*
  • Genes, Bacterial
  • Humans
  • Microbial Sensitivity Tests
  • Molecular Sequence Data
  • Mutation*
  • N-Acetylmuramoyl-L-alanine Amidase / genetics*
  • N-Acetylmuramoyl-L-alanine Amidase / metabolism
  • Sequence Analysis, DNA
  • beta-Lactamases / genetics
  • beta-Lactamases / metabolism*

Substances

  • Anti-Bacterial Agents
  • Bacterial Proteins
  • AmpR protein, Bacteria
  • Ceftazidime
  • AmpD protein, Bacteria
  • N-Acetylmuramoyl-L-alanine Amidase
  • AmpC beta-lactamases
  • beta-Lactamases

Associated data

  • GENBANK/AY789446
  • GENBANK/AY789447
  • GENBANK/AY789448