vanE gene cluster of vancomycin-resistant Enterococcus faecalis BM4405

J Bacteriol. 2002 Dec;184(23):6457-64. doi: 10.1128/JB.184.23.6457-6464.2002.

Abstract

Acquired VanE-type resistance to low levels of vancomycin (MIC = 16 microg/ml) in Enterococcus faecalis BM4405 is due to the inducible synthesis of peptidoglyean precursors terminating in D-alanine-D-serine (Fines,M., B. Prichon, P. Reynolds, D. Sahm, and P. Courvalin, Antimicrob. Agents Chemother. 43:2161-2164, 1999). A chromosomal location was assigned to the vanE operon by pulsed-field gel electrophoresis and hybridization, and its sequence was determined. Three genes, encoding the VanE ligase, the VanXYE DD-peptidase, and the VanTE serine racemase, that displayed 43 to 53% identity with the corresponding genes in the vanC operon were found. In addition, two genes coding for a two-component regulatory system, VanRE-VanSE, exhibiting 60 and 44% identity with VanR,-VanS, were present downstream from vanTE. However, because of a stop codon at position 78, VanSE was probably not functional. The five genes, with the same orientation, were shown to be cotranscribed by Northern analysis and reverse transcription-PCR. The vanE, vanXYE, and vanTE genes conferred inducible low-level resistance to vancomycin after cloning in E. faecalis JH2-2, probably following cross talk with a two-component regulatory system of the host.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anti-Bacterial Agents / pharmacology
  • Bacterial Proteins / genetics*
  • Bacterial Proteins / metabolism
  • Base Sequence
  • Carboxypeptidases / genetics*
  • Carboxypeptidases / metabolism
  • Cloning, Molecular
  • Drug Resistance, Microbial / genetics*
  • Endopeptidases / genetics*
  • Endopeptidases / metabolism
  • Enterococcus faecalis / drug effects*
  • Enterococcus faecalis / genetics
  • Gene Expression Regulation, Bacterial
  • Genes, Bacterial*
  • Humans
  • Ligases / genetics*
  • Ligases / metabolism
  • Membrane Proteins*
  • Molecular Sequence Data
  • Multigene Family
  • Racemases and Epimerases / genetics*
  • Racemases and Epimerases / metabolism
  • Sequence Analysis, DNA
  • Serine-Type D-Ala-D-Ala Carboxypeptidase*
  • Trans-Activators / genetics*
  • Trans-Activators / metabolism
  • Transcription, Genetic
  • Vancomycin / pharmacology
  • Vancomycin Resistance / genetics*

Substances

  • Anti-Bacterial Agents
  • Bacterial Proteins
  • Membrane Proteins
  • Trans-Activators
  • Vancomycin
  • Carboxypeptidases
  • Endopeptidases
  • Serine-Type D-Ala-D-Ala Carboxypeptidase
  • VanY protein, Bacteria
  • VanX dipeptidase
  • Racemases and Epimerases
  • VanT(E) protein, Enterococcus faecalis
  • Ligases
  • VanE protein, Enterococcus faecalis