SHV-34: an extended-spectrum beta-lactamase encoded by an epidemic plasmid

J Antimicrob Chemother. 2003 Dec;52(6):1015-7. doi: 10.1093/jac/dkh017. Epub 2003 Nov 12.


Objectives: To elucidate the causes for treatment failure in children given extended-spectrum cephalosporins.

Methods: During April 1998-March 2000, 18 isolates of members of the family Enterobacteriaceae, fulfilling microbiological criteria for carriage of extended-spectrum beta-lactamases (ESBLs) and carrying blaSHV, were isolated from paediatric inpatients. The collection was subjected to a retrospective molecular analysis.

Results: Three species were represented in the collection: Citrobacter koseri (one isolate), Escherichia coli (one isolate) and Klebsiella pneumoniae (16 isolates). A common plasmid was found in these bacteria, as judged by restriction endonuclease digestion. This was able to transfer an ESBL phenotype from donors to a laboratory strain of E. coli. Nucleotide sequence analysis revealed that this phenotype was associated with a new variant in blaSHV encoding SHV-34.

Conclusions: Analysis reveals the presence of an epidemic plasmid in this collection of bacteria. This carries a gene encoding the SHV-34 ESBL, described for the first time in this report. Nucleotide sequence analysis shows that there is a mutation from A-->G affecting the codon at amino acid position 64 (GAA-->GGA), changing the glutamic acid typically seen in this position to glycine.

MeSH terms

  • Amino Acid Substitution
  • Cephalosporins / therapeutic use
  • Child
  • Citrobacter koseri / drug effects
  • Citrobacter koseri / genetics
  • Conjugation, Genetic
  • Enterobacteriaceae / drug effects
  • Enterobacteriaceae / genetics*
  • Enterobacteriaceae Infections / drug therapy
  • Enterobacteriaceae Infections / epidemiology*
  • Enterobacteriaceae Infections / microbiology
  • Escherichia coli / drug effects
  • Escherichia coli / genetics
  • Escherichia coli Proteins / genetics*
  • Humans
  • Klebsiella pneumoniae / drug effects
  • Klebsiella pneumoniae / genetics
  • Microbial Sensitivity Tests
  • Phenotype
  • Plasmids / genetics*
  • Reverse Transcriptase Polymerase Chain Reaction
  • Treatment Failure
  • beta-Lactamases / genetics*


  • Cephalosporins
  • Escherichia coli Proteins
  • beta-Lactamases
  • beta-lactamase SHV-34, E coli