Wang Xue, Zhao Jianan, Ji Fang, Chang Han, Qin Jiao, Zhang Chenglin, Hu Guocheng, Zhu Jiayue, Yang Jianchun, Jia Zhongxin, Li Gang, Qin Jianhua, Wu Bin, Wang Chengmin
Guangdong Key Laboratory of Animal Conservation and Resource Utilization, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Institute of Zoology, Guangdong Academy of Science, Guangzhou, China.
College of Veterinary Medicine, Agricultural University of Hebei, Baoding, China.
Front Microbiol. 2021 Oct 27;12:754931. doi: 10.3389/fmicb.2021.754931. eCollection 2021.
Multiple-replicon resistance plasmids have become important carriers of resistance genes in Gram-negative bacteria, and the evolution of multiple-replicon plasmids is still not clear. Here, 56 isolates of isolated from different wild animals and environments between 2018 and 2020 were identified by phenotyping the micro-broth dilution method and were sequenced and analyzed for bacterial genome-wide association study. Our results revealed that the isolates from non-human sources showed more extensive drug resistance and especially strong resistance to ampicillin (up to 80.36%). The isolates from were particularly highly resistant to cephalosporins, chloramphenicol, levofloxacin, and sulfamethoxazole. Genomic analysis showed that the resistance plasmids in these isolates carried many antibiotic resistance genes. Further analysis of 69 plasmids demonstrated that 28 plasmids were multiple-replicon plasmids, mainly carrying beta-lactamase genes such as , , , , and . The analysis of plasmids carried by different isolates showed that might be an important multiple-replicon plasmid host. Plasmid skeleton and structure analyses showed that a multiple-replicon plasmid was formed by the fusion of two or more single plasmids, conferring strong adaptability to the antibiotic environment and continuously increasing the ability of drug-resistant isolates to spread around the world. In conclusion, multiple-replicon plasmids are better able to carry resistance genes than non-multiple-replicon plasmids, which may be an important mechanism underlying bacterial responses to environments with high-antibiotic pressure. This phenomenon will be highly significant for exploring bacterial resistance gene transmission and diffusion mechanisms in the future.
多复制子耐药质粒已成为革兰氏阴性菌中耐药基因的重要载体，而多复制子质粒的进化仍不明确。在此，通过微量肉汤稀释法进行表型鉴定，对2018年至2020年期间从不同野生动物和环境中分离出的56株菌株进行了测序，并进行细菌全基因组关联研究分析。我们的结果显示，来自非人类来源的菌株表现出更广泛的耐药性，尤其是对氨苄西林的耐药性很强（高达80.36%）。来自[具体来源未明确]的菌株对头孢菌素、氯霉素、左氧氟沙星和磺胺甲恶唑具有特别高的耐药性。基因组分析表明，这些菌株中的耐药质粒携带了许多抗生素耐药基因。对69个质粒的进一步分析表明，28个质粒是多复制子质粒，主要携带β-内酰胺酶基因，如[具体基因未明确列出]。对不同菌株携带的质粒分析表明，[具体菌株未明确]可能是一个重要的多复制子质粒宿主。质粒骨架和结构分析表明，一个多复制子质粒是由两个或更多个单质粒融合形成的，赋予了对抗生素环境的强大适应性，并不断增强耐药菌株在全球传播的能力。总之，多复制子质粒比非多复制子质粒更能携带耐药基因，这可能是细菌应对高抗生素压力环境的一个重要机制。这种现象对未来探索细菌耐药基因的传播和扩散机制具有高度重要意义。
