Detection of Tn917 Carrying erm(B) Gene in a Clinical Isolates of S. pyogenes Hassooni Hanan Raheem1, Jasim Hameed M.2,*, Farhan Abbas Aboud1, Alhusseiny Adil Hassan3 1Department of Biology, Faculty of Education for Pure Science, Diyala University, Iraq 2College of Biotechnology, Al-Nahrain University, Baghdad, Iraq 3Department of Internal Medicine, Faculty of Medicine, Diyala University, Iraq *Corresponding Author: Hameed M. Jasim, College of Biotechnology, Al-Nahrain University, Baghdad, Iraq, Email: hanan6319@gmail.com, drhmd_del@yahoo.com
Online published on 23 December, 2019. Abstract Background This study was conducted to investigate the genetic organization of erm-carrying Tn917 in clinical isolates of Streptococcus pyogenes. Tn917 is a nonconjugative transposon which is responsible for the spread of erythromycin resistance in bacterial isolates. Over the past two decades, erythromycin resistance rates have increased in S.pyogenes in many countries, To obtain information that may be useful in solving the spread of antimicrobial resistance, antibiotic-resistant genes can be identified as well as their association with mobile genetic elements. Material and Method A total of 22 isolates of S. pyogenes isolates collected from the infection of upper respiratory system were examined, first by detecting their antibiotic susceptibility against three different antibiotics groups (Macrolides, Tetracycline, and lincosamides) then genomic DNA was extracted from each isolate for detection Tn917 by using specific primers to amplify erm(B) gene carried by this transposable element. Results Results showed that there is a high level of resistance to erythromycin, (90.9%), then to Minocycline (68.1%), Lincomycin (59%), Tetracycline (54.5%), Clindamycin (50%), Azithromycin and Clarithromycin (36.3%), Doxycycline (31.8%) and then to Oxytetracycline (27.2%). Results also showed that five of S. pyogenes isolates were harboring Tn917 transposable element carrying erm gene. On the other hand, results showed that there are another isolates resistant to erythromycin that may possess a chromosomal or plasmid copy of the erythromycin resistance gene, or may the resistance caused by another structural erythromycin gene carried by other type of transposable elements rather than Tn917. Conclusion Our findings suggest that the isolates of S. pyogenes are harboring chromosomal copy of Tn917 conferring erythromycin resistance. One possible explanation for the presence of genes at different isolates is due to erm gene, which was most likely located on Tn917. Top Keywords Tn917, Erythromycin resistance, Streptococcus pyogenes, erm(B) gene. Top |