Genetic and biochemical characterization of CGB-1, an Ambler class B carbapenem-hydrolyzing beta-lactamase from Chryseobacterium gleum

Antimicrob Agents Chemother. 2002 Sep;46(9):2791-6. doi: 10.1128/AAC.46.9.2791-2796.2002.

Abstract

Chryseobacterium gleum (previously included in the Flavobacterium IIb species) is a gram-negative aerobe that is a source of nosocomial infections. An Ambler class B beta-lactamase gene was cloned and expressed in Escherichia coli from reference strain C. gleum CIP 103039 that had reduced susceptibility to expanded-spectrum cephalosporins and carbapenems. The purified beta-lactamase, CGB-1, with a pI value of 8.6 and a determined relative molecular mass of ca. 26 kDa, hydrolyzed penicillins; narrow- and expanded-spectrum cephalosporins; and carbapenems. CGB-1 was a novel member of the molecular subclass B1 of metallo-enzymes. It had 83 and 42% amino acid identity with IND-1 from Chryseobacterium indologenes and BlaB from C. meningosepticum, respectively. Thus, in addition to the previously characterized clavulanic acid-inhibited extended-spectrum beta-lactamase CGA-1 of Ambler class A, C. gleum produces a very likely chromosome-borne class B beta-lactamase.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Bacteria / drug effects
  • Bacteria / enzymology
  • Bacteria / genetics*
  • Base Sequence
  • Carbapenems / pharmacology*
  • Clavulanic Acid / pharmacology
  • Cloning, Molecular
  • Conjugation, Genetic
  • DNA, Bacterial / analysis
  • DNA, Recombinant / genetics
  • Drug Resistance
  • Enzyme Induction / drug effects
  • Enzyme Inhibitors / pharmacology
  • In Situ Hybridization
  • Isoelectric Focusing
  • Kinetics
  • Microbial Sensitivity Tests
  • Molecular Sequence Data
  • Plasmids / genetics
  • beta-Lactamases / genetics*

Substances

  • Carbapenems
  • DNA, Bacterial
  • DNA, Recombinant
  • Enzyme Inhibitors
  • Clavulanic Acid
  • beta-Lactamases
  • beta-lactamase CGB-1, Chryseobacterium gleum