基于“卫星质粒”的蜜蜂肠道菌群抗生素抗性基因动态传播及机制研究

环境残留的抗生素会导致蜜蜂共生肠道菌群中抗性基因的传播和积累，严重威胁了蜜蜂的健康。在这一过程中，具有细菌宿主广谱性的IncQ质粒对于抗生素抗性基因的传播起到重要促进作用。申请人前期研究表明，在Snodgrassella alvi单菌定植的西方蜜蜂肠道内，其携带的IncQ质粒可以通过产生“卫星质粒”的机制迅速降低对细菌宿主的负担，促进质粒和抗性基因的传播。然而“卫星质粒”机制对IncQ质粒在蜜蜂肠道菌群内传播稳定性的作用却尚未解析。本项目将针对带有抗生素抗性基因的IncQ质粒，着重研究其在蜜蜂肠道内不同菌种、不同菌株间的动态传播过程。通过肠道菌群宏基因组测序及转录组分析，结合基因工程手段和菌体表型验证，探明新型“卫星质粒”机制在质粒与不同细菌的适应性进化上的关键作用及分子机制。研究结果将为蜜蜂肠道内抗生素抗性基因传播的防控提供理论指导。

The exposure to the environmental antibiotic residue caused the accumulation of resistance genes in the honey bee gut microbiome and imposed potential threat to bee health. The broad host range IncQ plasmid plays a prominent role in the spread of antibiotic resistance genes. We have previously shown that the evolving of “satellite plasmid” reduced the burdensome of Snodgrassella alvi carrying the IncQ plasmid in bee gut. However, the role of the “satellite plasmid” arise playing in the spreading of IncQ plasmid among bacteria species and strains in the honey bee gut remains unknown. In this project, we will monitor the dynamic of the IncQ plasmid transmission among the bee gut microbial community. The arising of “satellite plasmid” and the adaptive mutations of those strain-plasmid associations will be detected, through which the mechanisms underlying the resistance genes dissemination will be explored.