College of Veterinary Medicine, Henan Agricultural Universitygrid.108266.b, Zhengzhou, China.
Microbiol Spectr. 2022 Feb 23;10(1):e0170621. doi: 10.1128/spectrum.01706-21. Epub 2022 Feb 16.
Two diverse conjugative plasmids can interact within bacterial cells. However, to the best of our knowledge, the interaction between -bearing IncFII plasmid and -carrying IncI2 plasmid colocated on the same bacterial host has not been reported. This study was initiated to explore the interaction and to analyze the reasons that these two plasmids are often coresident in multidrug-resistant Escherichia coli. To assess the interactions on plasmid stabilities, fitness costs, and transfer rates, we constructed two groups of isogenic derivatives, C600, C600, and C600 of E. coli C600 and J53, J53, and J53 of E. coli J53, respectively. We found that carriage of FII and I2 plasmids, independently and together, had not impaired the growth of the bacterial host. It was difficult for the single plasmid FII or I2 in E. coli C600 to reach stable persistence for a long time in an antibiotic-free environment, while the stability would be striking improved when they coresided. Meanwhile, plasmids FII and I2, whether together or apart, could notably enhance the fitness advantage of the host; moreover, E. coli coharboring plasmids FII and I2 presented more obvious fitness advantage than that carrying single plasmid FII. Coresident plasmids FII and I2 could accelerate horizontal cotransfer by conjugation. The transfer rates from a strain carrying coresident FII and I2 plasmids increased significantly when it mated with a recipient cell carrying one of them. Our findings highlight the advantages of coinhabitant FII and I2 plasmids in E. coli to drive the persistence and spread of plasmid-carried and genes, although the molecular mechanisms of their coresidence warrant further study. More and more carry both and , which are usually located on IncFII-type and IncI2-type plasmids in the same bacterial host, respectively. However, the study on advantages of coresident plasmids in bacterial host is still sparse. Here, we investigated the stability, fitness cost, and cotransfer traits associated with coresident IncFII-type and IncI2-type plasmids in E. coli. Our results show that coinhabitant plasmids in E. coli are more stable, confer more fitness advantages, and are easier to transfer and cotransfer than a single plasmid IncFII or IncI2. Our findings confirm the advantages of coresident plasmids of -bearing IncFII and -bearing IncI2 in clinical E. coli, which will pose a serious threat to clinical therapy and public health.
两种不同的可接合质粒可以在细菌细胞内相互作用。然而，据我们所知，-携带的 IncFII 质粒和-携带的 IncI2 质粒在同一细菌宿主中共存的相互作用尚未被报道。本研究旨在探索这种相互作用，并分析这两种质粒经常共存于多药耐药大肠杆菌中的原因。为了评估质粒稳定性、适应性成本和转移率的相互作用，我们构建了两组同基因衍生物，大肠杆菌 C600 的 C600、C600 和 C600，以及大肠杆菌 J53 的 J53、J53 和 J53。我们发现，单独携带 FII 和 I2 质粒，或共同携带这两种质粒，都没有损害细菌宿主的生长。在没有抗生素的环境中，单个质粒 FII 或 I2 在大肠杆菌 C600 中很难长时间稳定存在，而当它们共存时，稳定性会显著提高。同时，FII 和 I2 质粒无论是单独携带还是共同携带，都能显著提高宿主的适应性优势；此外，同时携带质粒 FII 和 I2 的大肠杆菌比单独携带质粒 FII 的大肠杆菌具有更明显的适应性优势。共存的 FII 和 I2 质粒可以通过接合加速水平共转移。当携带共存 FII 和 I2 质粒的菌株与携带其中一种质粒的受体细胞交配时，其转移率显著增加。我们的研究结果强调了 FII 和 I2 质粒在大肠杆菌中的共存优势，有助于驱动携带和的质粒的持久性和传播，尽管它们共存的分子机制仍有待进一步研究。越来越多的大肠杆菌同时携带和，它们通常分别位于 IncFII 型和 IncI2 型质粒上。然而，关于细菌宿主中共存质粒优势的研究仍然很少。在这里，我们研究了大肠杆菌中携带 IncFII 型和 IncI2 型质粒的共存 IncFII 型和 IncI2 型质粒的稳定性、适应性成本和共转移特性。我们的结果表明，与单个 IncFII 或 IncI2 质粒相比，大肠杆菌中共存的质粒更稳定，赋予更多的适应性优势，更容易转移和共转移。我们的研究结果证实了临床大肠杆菌中携带的 IncFII 质粒和携带的 IncI2 质粒的共存优势，这将对临床治疗和公共健康构成严重威胁。
