Effects of Ser130Gly and Asp240Lys substitutions in extended-spectrum beta-lactamase CTX-M-9

Antimicrob Agents Chemother. 2003 Sep;47(9):2958-61. doi: 10.1128/AAC.47.9.2958-2961.2003.

Abstract

In CTX-M-9 extended-spectrum beta-lactamases (ESBLs), an S130G mutation induced a 40- to 650-fold increase in 50% inhibitory concentrations but decreased hydrolytic activity against cefotaxime. A D240K mutation did not modify enzymatic efficiency against ceftazidime. Residue K240 could interact with Q270 and therefore not with ceftazidime, in contrast with what was observed with certain TEM/SHV-type ESBLs.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Substitution
  • Anti-Bacterial Agents / pharmacology
  • Cefotaxime / metabolism
  • Ceftazidime / pharmacology
  • Cephalosporins / pharmacology
  • Escherichia coli Proteins*
  • Hydrolysis
  • Kinetics
  • Models, Molecular
  • Molecular Conformation
  • Mutation / genetics
  • Mutation / physiology
  • Plasmids / genetics
  • beta-Lactamases / genetics*
  • beta-Lactamases / metabolism*

Substances

  • Anti-Bacterial Agents
  • Cephalosporins
  • Escherichia coli Proteins
  • Ceftazidime
  • CTX-M-9 protein, E coli
  • beta-Lactamases
  • Cefotaxime