Characterization of the plasmid mediated beta-lactamase BIL-1

J Antimicrob Chemother. 1992 Aug;30(2):119-27. doi: 10.1093/jac/30.2.119.


A multi-resistant strain of Escherichia coli isolated from a patient from Pakistan was shown to possess a new plasmid-mediated beta-lactamase. This enzyme, designated BIL-1, conferred resistance to extended-spectrum cephalosporins such as cefotaxime and ceftazidime. However, unlike other plasmid-mediated beta-lactamases capable of conferring resistance to these drugs, the BIL-1 was not a member of the TEM or SHV group of plasmid-mediated beta-lactamases and it also conferred resistance to beta-lactam drugs in combination with beta-lactamase inhibitors (i.e. clavulanic acid). The biochemical properties of the enzyme suggest that BIL-1 is related to the Richmond & Sykes Class I chromosomal beta-lactamases. Its inhibition properties by various beta-lactam drugs are similar to the inhibition properties of the chromosomally-encoded P99 enzyme of Enterobacter cloacae.

MeSH terms

  • Anti-Bacterial Agents / metabolism
  • Anti-Bacterial Agents / pharmacology*
  • Cephalosporins / pharmacology
  • Escherichia coli / drug effects
  • Escherichia coli / enzymology*
  • Isoelectric Focusing
  • Microbial Sensitivity Tests
  • Plasmids
  • beta-Lactamase Inhibitors
  • beta-Lactamases / genetics*


  • Anti-Bacterial Agents
  • Cephalosporins
  • beta-Lactamase Inhibitors
  • beta-Lactamases