Zhang Gang, Cui Qinna, Li Jianjuan, Guo Ruiliang, Leclercq Sébastien Olivier, Du Lifeng, Tang Na, Song Yuqin, Wang Chao, Zhao Fangqing, Feng Jie
State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China.
College of Life Science, University of Chinese Academy of Sciences, Beijing, China.
Front Microbiol. 2022 Aug 1;13:905865. doi: 10.3389/fmicb.2022.905865. eCollection 2022.
In the worldwide health threat posed by antibiotic-resistant bacterial pathogens, mobile genetic elements (MGEs) play a critical role in favoring the dissemination of resistance genes. Among them, the genomic island GI and the IS-related element CR2 unit are believed to participate in this dissemination. However, the mobility of the two elements has not yet been demonstrated. Here, we found that the GI and CR2 units can excise from the host chromosomal attachment site () in . Through establishing a two-plasmid mobilization system composed of a donor plasmid bearing the GI and a trap plasmid harboring the in -deficient , we reveal that the integrase of GI can perform the excision and integration of GI and CR2 unit by site-specific recombination between core sites. Furthermore, we demonstrate that the integrase and the sites are required for mobility through knockout experiments. Our findings provide the first experimental characterization of the mobility of GI and CR2 units mediated by integrase. They also suggest a potential and unappreciated role of the GI integrase family in the dissemination of CR2 units carrying various resistance determinants in between.
在抗生素耐药性细菌病原体构成的全球健康威胁中，移动遗传元件（MGEs）在促进耐药基因传播方面发挥着关键作用。其中，基因组岛GI和与插入序列相关的元件CR2单元被认为参与了这种传播。然而，这两种元件的移动性尚未得到证实。在这里，我们发现GI和CR2单元可以从宿主染色体附着位点（）在中切除。通过建立一个由携带GI的供体质粒和在缺陷中携带的捕获质粒组成的双质粒动员系统，我们揭示GI的整合酶可以通过核心位点之间的位点特异性重组来进行GI和CR2单元的切除和整合。此外，我们通过基因敲除实验证明整合酶和位点对于移动性是必需的。我们的发现首次对由整合酶介导的GI和CR2单元的移动性进行了实验表征。它们还表明GI整合酶家族在携带各种抗性决定簇的CR2单元在之间传播中具有潜在的、未被认识到的作用。
