Detection of virulence factors in high-level gentamicin-resistant Enterococcus faecalis and Enterococcus faecium isolates from a Tunisian hospital
- Klibi, N. 4
- Ben Slama, K. 4
- Sàenz, Y. 1
- Masmoudi, A. 3
- Zanetti, S. 2
- Sechi, L.A. 2
- Boudabous, A. 4
- Torres, C. 1
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1
Universidad de La Rioja
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2
University of Sassari
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3
Hôpital La Rabta
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4
Université de Tunis El Manar
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ISSN: 0008-4166
Argitalpen urtea: 2007
Alea: 53
Zenbakia: 3
Orrialdeak: 372-379
Mota: Artikulua
Beste argitalpen batzuk: Canadian Journal of Microbiology
Laburpena
Phenotypic and genotypic determination of virulence factors were carried out in 46 high-level gentamicin-resistant (HLGR) clinical Enterococcus faecalis (n = 34) and Enterococcus faecium (n = 12) isolates recovered from different patients in La Rabta Hospital in Tunis, Tunisia, between 2000 and 2003 (all these isolates harboured the aac(6′)-aph(2″) gene). The genes encoding virulence factors (agg, gelE, ace, cylLLS, esp, cpd, and fsrB) were analysed by PCR and sequencing. The production of gelatinase and hemolysin, the adherence to caco-2 and hep-2 cells, and the capacity for biofilm formation were investigated in all 46 HLGR enterococci. The percentages of E. faecalis isolates harbouring virulence genes were as follows: gelE, cpd, and ace (100%); fsrB (62%); agg (56%); cylLLS (41.2%); and esp (26.5%). The only virulence gene detected among the 12 HLGR E. faecium isolates was esp (58%). Gelatinase activity was detected in 22 of the 34 E. faecalis isolates (65%, most of them with the gelE+-fsrB+ genotype); the remaining 12 isolates were gelatinase-negative (with the gelE +-fsrR- genotype and the deletion of a 23.9 kb fragment of the fsr locus). Overall, 64% of the cylLLS-containing E. faecalis isolates showed β-hemolysis. A high proportion of our HLGR E. faecalis isolates, in contrast to E. faecium, showed moderate or strong biofilm formation or adherence to caco-2 and hep-2 cells. © 2007 NRC.