The PavA-like fibronectin-binding protein of Enterococcus faecalis, EfbA, is important for virulence in a mouse model of ascending urinary tract infection

J Infect Dis. 2012 Sep 15;206(6):952-60. doi: 10.1093/infdis/jis440. Epub 2012 Jul 10.

Abstract

Enterococcus faecalis is an established nosocomial pathogen, yet the pathogenesis of enterococcal infections, particularly of urinary tract infections (UTIs), remains to be fully elucidated. Fibronectin-binding proteins have been identified as potent adhesins in pathogenic Gram-positive cocci. Here, we characterized EfbA, which is encoded by the enterococcal orthologue of Streptococcus pneumoniae pavA. Similar to PavA, the anchorless EfbA protein was localized to the enterococcal cell outer surface and bound to immobilized human fibronectin. In addition to abrogated EfbA expression, deletion of the efbA gene eliminated EfbA from the cell surface and drastically reduced the enterococcal cell binding to immobilized fibronectin. The ΔefbA deletion mutant was highly attenuated vs wild-type in a murine ascending UTI model, consistent with an increased tropism for the kidney relative to the bladder. These results provide the first evidence that EfbA of E. faecalis plays a role in UTIs, probably contributing to the pathogenesis in this site.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Bacterial Adhesion
  • Bacterial Proteins / chemistry
  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism*
  • Enterococcus faecalis / metabolism
  • Enterococcus faecalis / pathogenicity*
  • Enzyme-Linked Immunosorbent Assay / methods
  • Female
  • Fibronectins / metabolism
  • Fluorescent Antibody Technique
  • Gene Deletion
  • Gene Expression Regulation, Bacterial / physiology
  • Gram-Positive Bacterial Infections / microbiology*
  • Immunoblotting
  • Membrane Proteins / metabolism
  • Mice
  • Microscopy, Immunoelectron
  • Protein Binding
  • Recombinant Proteins
  • Urinary Tract Infections / microbiology*
  • Virulence

Substances

  • Bacterial Proteins
  • Fibronectins
  • Membrane Proteins
  • PavA protein, Streptococcus pneumoniae
  • Recombinant Proteins