Genetic diversity of carbapenem-hydrolyzing metallo-beta-lactamases from Chryseobacterium (Flavobacterium) indologenes

Antimicrob Agents Chemother. 2000 Nov;44(11):3028-34. doi: 10.1128/AAC.44.11.3028-3034.2000.


The class B carbapenem-hydrolyzing beta-lactamase IND-1 has been characterized for Chryseobacterium indologenes strain 001. With internal primers for the bla gene for IND-1 (bla(IND-1)) and an internal bla(IND-1) probe, PCR amplifications failed, while hybridization results were positive when DNA from another C. indologenes isolate, strain CIP101026, was used as a template. Thus, a bla(IND)-related gene was cloned from this C. indologenes reference strain. Sequencing of the insert of a recombinant plasmid conferring resistance to carbapenems revealed an open reading frame with a G + C content of 39.9% and coding for a 243-amino-acid preprotein named IND-2. IND-2 shared 80% amino acid identity with IND-1 and had a similar broad-spectrum resistance profile, including resistance to carbapenems. It was classified in functional subgroup 3a of class B carbapenem-hydrolyzing beta-lactamases. IND-1 and IND-2, despite their genetic diversity, possessed similar kinetic parameters, except that ceftazidime was hydrolyzed less by IND-2. To obtain the entire bla(IND)-related gene sequences of eight other C. indologenes isolates, PCR was performed using internal and external primers, followed by inverse PCR techniques. The likely chromosome-mediated metallo-beta-lactamases of the 10 C. indologenes isolates were divided into several groups and subgroups. IND-1, IND-2, IND-2a, IND-3, and IND-4 shared 77 to 99% amino acid identity.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Anti-Bacterial Agents / pharmacology
  • Carbapenems / metabolism
  • Flavobacterium / drug effects
  • Flavobacterium / enzymology
  • Flavobacterium / genetics*
  • Genetic Variation
  • Humans
  • Hydrolysis
  • Microbial Sensitivity Tests
  • Molecular Sequence Data
  • Sequence Homology, Amino Acid
  • beta-Lactamases / genetics*
  • beta-Lactamases / metabolism


  • Anti-Bacterial Agents
  • Carbapenems
  • beta-Lactamases