ABSTRACT

Background: The Tn916-Tn1545 family of Integrative Conjugative Elements (ICE) are mobile genetic elements (MGEs) that play a role in the spread of antibiotic resistance genes. The Tn916 harbors the tetracycline resistance gene tet(M) and it has been reported in various bacterial species. The increase in the levels of tetracycline resistance among oral streptococci is of great concern primarily due to the abundance of these species in the oral cavity and their ability to act as reservoirs for antibiotic resistance genes.Methods: In the current study, we screened 100 Norwegian clinical oral streptococcal isolates for the presence and diversity of the Tn916-Tn1545 family. In addition, we investigated the transferability the elements, and the associated transfer frequencies.Results: We observed that 21 isolates harboured the Tn916-Tn1545 family and that two of these elements were the novel Tn6815 and Tn6816. The most prevalent member of the Tn916 -Tn1545 family observed in the Norwegian clinical oral streptococcal isolates was the wild type Tn916.Conclusion: The detection of other members of this family of ICE and varying transfer frequencies suggests high versatility of the Tn916 element in oral streptococci in Norway.

摘要

背景：Tn 916 -Tn 1545整合结合元件家族（ICE）是可移动的遗传元件（MGE），在抗生素抗性基因的传播中发挥作用。Tn 916带有四环素抗性基因tet（M），并且在各种细菌中都有报道。口腔链球菌中四环素耐药性水平的提高引起了极大的关注，这主要是由于这些物种在口腔中的丰富性以及它们作为抗生素抗性基因的储库的能力。方法：在本研究中，我们筛选了100例挪威临床口腔链球菌分离株中Tn 916 -Tn的存在和多样性1545年家庭。此外，我们研究了元素的可转移性以及相关的转移频率。结果：我们观察到21个分离株含有Tn 916 - Tn 1545家族，其中两个是新的Tn 6815和Tn 6816。在挪威临床口腔链球菌分离物中观察到的Tn 916 -Tn 1545家族中最普遍的成员是野生型Tn 916。结论：该ICE家族其他成员的检测和不同的转移频率表明，挪威口腔链球菌中的Tn 916元素具有高度的通用性。