Abstract
BACKGROUND AND AIMS: Enterococci are among resistant microorganisms to antibiotics and are responsible for some of acute gingival infections. This study aimed at molecular evaluation of gentamicin-resistant enterococcus species and determining the resistance genes. MATERIALS AND METHODS: Clinical samples were cultured on BHI medium and enterococci were isolated by specific methods and antibiograms were prepared. DNA was derived from gentamicin-resistant species by alkaline lysis method and replicated by PCR method. Four gentamicin-resistant genes were evaluated by electrophoresis method on agarose gel. RESULTS: From 105 Enterococcus faecalis isolates, 36.2% and from 38 Enterococcus faecium isolates, 78.2% were resistant to gentamicin. 60% of these species bore aac (6')- le - aph(2")- la gene. ph(2")- Ib,Ic,Id genes were not seen in any of the evaluated species. CONCLUSION: In gentamicin-resistant species of E. faecalis and E. faecium, the aac (6')- le - aph(2")- la gene was identified as the main cause of resistance.