Variety of TEM-, SHV-, and CTX-M-type Beta-Lactamases Present in Recent Clinical Isolates of Escherichia Coli, Klebsiella Pneumoniae, and Enterobacter Cloacae From Taiwan

Microb Drug Resist. Spring 2005;11(1):31-9. doi: 10.1089/mdr.2005.11.31.


A total of 171 hospitals' isolates of E. coli, K. pneumoniae, and E. cloacae with a minimum inhibitory concentration (MIC) of > or =2 microg/ml for ceftazidime or cefotaxime were evaluated for the production of beta-lactamases. PCR amplification with specific primers for the bla (SHV), bla (TEM), and bla (CTX) genes revealed that a total of 53, 81, and 43 of these genes were amplified, respectively. Sequencing results confirmed that TEM-1, CTX-M-3 and -14, SHV-1, -5, -11, -12, and -33, OXY-1a, and LEN-1 were presented among these isolates. No specific large cluster of isolates carried the same beta-lactamases, indicating the wide diversity of the collected strains. Plasmid spread between E. coli and K. pneumoniae was identified in few isolates. Combinations of TEM, SHV, and CTX beta-lactamase genes, including extended-spectrum beta-lactamase genes, were observed in all three species.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Enterobacteriaceae / drug effects*
  • Enterobacteriaceae / enzymology
  • Escherichia coli / drug effects
  • Escherichia coli / enzymology
  • Humans
  • Klebsiella / drug effects
  • Klebsiella / enzymology
  • Klebsiella pneumoniae / drug effects
  • Klebsiella pneumoniae / enzymology
  • Microbial Sensitivity Tests
  • Phylogeny
  • Polymerase Chain Reaction
  • Ribotyping
  • Sequence Analysis, DNA
  • Taiwan
  • beta-Lactam Resistance*
  • beta-Lactamases / isolation & purification*


  • beta-lactamase CTX-M-10
  • beta-lactamase SHV-2
  • beta-lactamase TEM-4
  • beta-Lactamases