In vivo testing of an Enterococcus faecalis efaA mutant and use of efaA homologs for species identification

Kavindra V. Singh, Teresa M. Coque, George M. Weinstock, Barbara E. Murray

Research output: Contribution to journalArticlepeer-review

154 Scopus citations


Disruption of the previously described efaA (from Enterococcus faecalis antigen A) gene was generated in E. faecalis strain OG1RF and loss of an ~37-kDa immunoreactive band from the mutant was demonstrated in Western blots. In a mouse peritonitis model, mice infected with the efaA(fs) (fs=from Enterococcus faecalis) mutant showed more prolonged survival than mice infected with the parent strain OG1RF. These results suggest that efaA(fs) encodes a function important for infection of mice by enterococci. An efaA-like gene was also identified in E. faecium DNA libraries and its deduced amino acid sequence showed 73% similarity to EfaA of E. faecalis and 42-63% similarities to a group of streptococcal virulence and adhesion associated proteins that are components of ATP-binding cassette transport systems. Intragenic probes representing efaA(fs), recA(fs), efaA(fm) (fm=from E. faecium) and gyrA(fm) were tested for their ability to identify E. faecalis and E. faecium using colony lysates of 133 enterococci and one Streptococcus sp. Probes of E. faecium and E. faecalis origin hybridized to all isolates of E. faecium and E. faecalis, respectively, regardless of their clinical source but not to any of 29 other enterococci. These results suggest that the use of gene probes may prove helpful in identification of isolates of E. faecium and E. faecalis. Copyright (C) 1998 Published by Elsevier Science B.V.

Original languageEnglish (US)
Pages (from-to)323-331
Number of pages9
JournalFEMS Immunology and Medical Microbiology
Issue number4
StatePublished - Aug 1998


  • Enterococcus
  • Species identification
  • Virulence
  • efaA mutant

ASJC Scopus subject areas

  • Immunology and Allergy
  • Microbiology
  • Immunology
  • Microbiology (medical)
  • Infectious Diseases


Dive into the research topics of 'In vivo testing of an Enterococcus faecalis efaA mutant and use of efaA homologs for species identification'. Together they form a unique fingerprint.

Cite this