A Potential Virulence Gene,hyl_Efm, Predominates inEnterococcus faeciumof Clinical Origin

Abstract

An open reading frame (hyl(Efm)) with homologies to previously described hyaluronidase genes has been identified in nonstool isolates of Enterococcus faecium. E. faecium isolates (n=577) from diverse sources were screened for the presence of hyl(Efm) and esp(Efm), a putative virulence gene associated with epidemic E. faecium strains. The presence of esp(Efm) was roughly twice that of hyl(Efm), but both were found primarily in vancomycin-resistant E. faecium isolates in nonstool cultures obtained from patients hospitalized in the United States. These data suggest that specific E. faecium strains may be enriched in determinants that make them more likely to cause clinical infections. Differences in the prevalence of these strains may help explain variations in the clinical importance of multiresistant E. faecium across different continents.

Determination of virulence and multidrug resistance genes with polymerase chain reaction method in vancomycin-sensitive and -resistant enterococci isolated from clinical samples*

“…Wıth regard to the presence of the hyl virulence gene area, the rate of hyl was 4%-7% in European countries (8,24,34,35), 17.2%-100% in continental America (27,36,37), and 53% in Saudi Arabia (38) in VSE strains. We found that 12.9% of all isolates had the hyl gene in this study.…”

“…Although esp is common in E. faecalis isolates, it is more common in hospital-acquired E. faecium isolates in particular (4). The rate of esp expression in enterococcal isolates is 49.5%-77% (21)(22)(23) in Asian countries, 33%-65% (8,24,25) in European countries, and 33%-76% in continental America (26)(27)(28). A study (29) conducted in Turkey reported that this rate was 25.6%.…”

Phenotypic Safety Assessment and Molecular Characterization of Enterococcus feacium MBTU-P1F1 (KF745071) from Infant feces

“…The hyl genes have shown to increase lethality in murine peritonitis model and according to Rice et al, (2003) this gene is never present in community associated clade. The hyl efm gene is predominantly seen in Vancomycin and Ampicillin resistant strains which come under hospital associated clade.…”

Guidance on the safety assessment ofEnterococcus faeciumin animal nutrition

“…The esp gene has an important role in biofilm formation of E. faecium (Heikens et al, 2007) and has been experimentally proven to contribute to endocarditis (Heikens et al, 2011) and urinary tract infections (Leendertse et al, 2009) in animal models. The esp gene is common among ampicillin and vancomycin resistant E. faecium isolates (Rice et al, 2003;Vankerchoven et al, 2004).…”