Lyra de Holanda Fonseca Douglas, Scheunemann Gaby Soares, Fortes Bruna Nakanishi, Ishida Kelly, Galhardo Rodrigo S
Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil.
Microbiol Spectr. 2025 Jul;13(7):e0033925. doi: 10.1128/spectrum.00339-25. Epub 2025 May 23.
Integrative and conjugative elements (ICEs) of the SXT/R391 family are mobile genetic elements that integrate into the bacterial host chromosome and can be transferred horizontally, spreading antimicrobial resistance genes. Our study aimed to evaluate aspects of the relationship between ICEJpn1, one of the most widespread SXT/R391 variants, with its natural host . For this investigation, we used isogenic strains (containing or not the ICEJpn1) that enabled us to evaluate the influence of this element on several physiological aspects of as well as the effect of different genetic backgrounds on the conjugative transmission of the element. ICEJpn1 did not impact the fitness, self-recognition, swarming, pathogenicity, and persistence abilities of this bacterium but increased biofilm formation in one strain. Additionally, conjugative transfer of the element to is widely variable when different strains are used as donors in mating assays. Our results indicate that ICEJpn1 has no adverse effects on the physiology or pathogenicity of , reflecting a stable association between this element and its host. Furthermore, the findings support the notion that ICE transfer between bacteria is influenced not only by element-specific regulators but also by strain-specific factors.IMPORTANCEMobile genetic elements play a key role in the spread of antimicrobial resistance, raising concerns about multidrug-resistant bacteria, yet their interactions with bacterial hosts are not well characterized. This study explores the relationship between ICEJpn1, a globally distributed SXT/R391 integrative and conjugative element (ICE), and its natural host , revealing minimal effects on bacterial fitness and pathogenicity. Nevertheless, strain-specific factors significantly influence conjugative transfer. These findings highlight the need for further research on host-dependent regulatory mechanisms that drive the spread of these elements. Understanding these dynamics is essential for developing strategies to mitigate the dissemination of antibiotic resistance in clinically relevant bacterial populations.
SXT/R391家族的整合与接合元件（ICEs）是可移动遗传元件，可整合到细菌宿主染色体中，并能水平转移，传播抗菌抗性基因。我们的研究旨在评估最广泛传播的SXT/R391变体之一ICEJpn1与其天然宿主之间关系的各个方面。为了进行这项研究，我们使用了同基因菌株（含有或不含有ICEJpn1），这使我们能够评估该元件对[细菌名称]几个生理方面的影响，以及不同[细菌名称]遗传背景对该元件接合传递的影响。ICEJpn1对这种细菌的适应性、自我识别、群体运动、致病性和持久性能力没有影响，但在一个菌株中增加了生物膜的形成。此外，当在交配试验中使用不同的[细菌名称]菌株作为供体时，该元件向[细菌名称]的接合转移差异很大。我们的结果表明，ICEJpn1对[细菌名称]的生理或致病性没有不利影响，反映了该元件与其宿主之间的稳定关联。此外，研究结果支持这样一种观点，即细菌之间的ICE转移不仅受元件特异性调节因子的影响，还受菌株特异性因素的影响。
重要性
可移动遗传元件在抗菌抗性传播中起关键作用，引发了对多重耐药细菌的担忧，但其与细菌宿主的相互作用尚未得到充分表征。本研究探讨了全球分布的SXT/R391整合与接合元件（ICE）ICEJpn1与其天然宿主[细菌名称]之间的关系，揭示了对细菌适应性和致病性的影响极小。然而，菌株特异性因素显著影响接合转移。这些发现凸显了对驱动这些元件传播的宿主依赖性调节机制进行进一步研究的必要性。了解这些动态对于制定策略以减轻临床相关细菌群体中抗生素抗性的传播至关重要。
