Substitution of alanine for aspartate at position 179 in the SHV-6 extended-spectrum beta-lactamase

FEMS Microbiol Lett. 1997 Jul 1;152(1):163-7. doi: 10.1016/s0378-1097(97)00196-1.


SHV-6 was previously identified by its susceptibility pattern and biochemical criteria in a clinical isolate of Klebsiella pneumoniae which was resistant to ceftazidime. It contains only a single point difference with the beta laSHV-1 gene as determined by PCR amplification and nucleotide sequencing. This is the result of a single amino acid substitution, Ala for Asp, at position 179. Directed mutagenesis experiments have shown this substitution to confer selective resistance to ceftazidime in the TEM family.

MeSH terms

  • Amino Acid Sequence
  • Base Sequence
  • Ceftazidime / pharmacology
  • Klebsiella pneumoniae / enzymology*
  • Microbial Sensitivity Tests
  • Molecular Sequence Data
  • Structure-Activity Relationship
  • beta-Lactamases / chemistry*
  • beta-Lactamases / genetics
  • beta-Lactamases / physiology


  • Ceftazidime
  • beta-Lactamases

Associated data

  • GENBANK/Y11069