The rapid spread of antibiotic-resistance genes (ARGs) in Enterococcus faecalis (E. faecalis) poses a great challenge to human health and ecological and environmental safety. Therefore, it is important to control the spread of ARGs. In this study, we observed that the addition of 5 μg/mL docosahexaenoic acid (DHA) reduced the conjugative transfer of pCF10 plasmid by more than 95% in E. faecalis. DHA disturbed the pheromone transport by inhibiting the mRNA levels of the prgZ gene, causing the iCF10 pheromone to accumulate in the donor bacteria and bond to the PrgX receptor to form an inhibitory phase, which resulted in the down-regulation of the expression of genes related to conjugative transfer, inhibiting biofilm formation, reducing bacterial adhesion and thus inhibiting conjugative transfer. Collectively, DHA exhibited an admirable inhibitory effect on the transfer of ARGs in E. faecalis. This study provided a technical option to control the transfer of ARGs.

粪肠球菌（E. faecalis ）中抗生素抗性基因（ARGs）的快速传播给人类健康和生态环境安全带来了巨大挑战。因此，控制 ARG 的传播非常重要。在这项研究中，我们观察到添加 5  μg/mL 二十二碳六烯酸 (DHA) 后，pCF10 质粒在粪肠球菌中的接合转移减少了 95% 以上。DHA 通过抑制prgZ的 mRNA 水平来干扰信息素转运基因，导致 iCF10 信息素在供体细菌中积累并与 PrgX 受体结合形成抑制相，导致结合转移相关基因表达下调，抑制生物膜形成，减少细菌粘附，从而抑制结合转移。总的来说，DHA 对粪肠球菌中 ARG 的转移表现出令人钦佩的抑制作用。该研究提供了控制 ARGs 转移的技术选择。