Balaei Gajan Esrafil, Akbarzadeh Parisa, Harasi Bahram, Moosavi Zohreh
Dentist, Department of Community Dentistry, Faculty of Dentistry, Tabriz University of Medical Sciences, Tabriz, Iran.
J Dent Res Dent Clin Dent Prospects. 2011 Winter;5(1):23-6. doi: 10.5681/joddd.2011.005. Epub 2011 Mar 18.
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.
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.
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.
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.
肠球菌属于对抗生素耐药的微生物，可引发一些急性牙龈感染。本研究旨在对庆大霉素耐药肠球菌进行分子评估并确定耐药基因。
临床样本在脑心浸液培养基上培养，采用特定方法分离肠球菌并制备抗菌谱。通过碱性裂解法从庆大霉素耐药菌株中提取DNA，采用PCR法进行扩增。通过琼脂糖凝胶电泳法评估四种庆大霉素耐药基因。
在105株粪肠球菌分离株中，36.2%对庆大霉素耐药；在38株屎肠球菌分离株中，78.2%对庆大霉素耐药。这些菌株中有60%携带aac(6')-le-aph(2")-la基因。在所评估的任何菌株中均未发现ph(2")-Ib、Ic、Id基因。
在对庆大霉素耐药的粪肠球菌和屎肠球菌中，aac(6')-le-aph(2")-la基因被确定为主要耐药原因。
