title: Adhesion and virulence factor properties of Enterococci isolated from clinical samples in Iran.
abstract: BACKGROUND
  Enterococci rank among leading causes of nosocomial bacteremia, urinary tract infections and community acquired endocarditis. The aim of the present study was to investigate the presence of virulence factors in Enterococci strains isolated from clinical samples in Iranian Educational hospitals.
  
  
  METHODS
  Presence of aggregation substance (asa), extracellular surface protein (esp), Enterococcus faecalis antigen A (efaA), adhesin of collagen from E. faecalis (ace), endocarditis and biofilm-associated pilli (ebp) as colonization factors and cytolysin (cyl), gelatinase (gel) and hyaloronidase (hyl) as secretary factors were investigated in isolates. A total of 201 clinical isolates of Enterococci were collected in 2009-2010 from eight educational hospitals. After deoxyribonucleic acid extraction, they were examined for presence of virulence factors by polymerase chain reaction.
  
  
  RESULTS
  E. faecalis and Enterococcus faecium were isolated from 56.9% to 43.1%, respectively. Resistance to vancomycin and gentamicin were 33.8% and 83.9% in E. faecium isolates and 16.3% and 88.1% in E. faecalis isolates respectively. Colonization factors were found to be more prevalent in E. faecalis isolates and almost all isolates of E. faecalis had ace, ebp and efaA genes. Esp gene had a higher rate of distribution in Enterococci isolates (75.1%) in this study compared with previous studies. One of E. faecalis isolates contained hyl gene, but 38.8% of E. faecium isolates had it. Mutual exclusive were present between hyl and efaA in all E. faecium isolates and 69.7% of E. faecium hyl - positive isolates were esp positive.
  
  
  CONCLUSIONS
  According to these results, virulence genes were more prevalent in E. faecalis isolates and E. faecalis had more potential pathogenesis for initiating an infection; however because of E. faeciums higher antibiotic resistance, we have been facing higher E. faecium infections in hospitalized patients.
authors.affiliation: Department of Medical Bacteriology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran.
authors.forename: Hossein Samadi
authors.initials: HS
authors.lastname: Kafil
authors.forename: Ashraf Mohabati
authors.initials: AM
authors.lastname: Mobarez
authors.forename: Mehdi Fourozandeh
authors.initials: MF
authors.lastname: Moghadam
mesh_terms: D001422:Bacterial Adhesion; D004269:DNA, Bacterial / Q000235:genetics / Q000302:isolation & purification; D013293:Enterococcus faecalis / Q000235:genetics / Q000302:isolation & purification / Q000472:pathogenicity* / Q000502:physiology*; D016984:Enterococcus faecium / Q000235:genetics / Q000302:isolation & purification / Q000472:pathogenicity* / Q000502:physiology*; D005260:Female; D016908:Gram-Positive Bacterial Infections / Q000382:microbiology; D006784:Hospitals, Teaching; D006801:Humans; D007492:Iran; D008297:Male; D016133:Polymerase Chain Reaction; D014774:Virulence; D037521:Virulence Factors / Q000235:genetics*
chemical_list: D004269:DNA, Bacterial; D037521:Virulence Factors