Recent studies suggest that quorum-sensing molecules may play a role in gut microbiota-host crosstalk. However, whether microbiota produces quorum-sensing molecules and whether those molecules can trans-kingdom transport to the host are still unknown. Here, we develop a UPLC-MS/MS-based assay to screen the 27 N-acyl homoserine lactones (AHLs) in the gut microbiota and host. Various AHL molecules are exclusively detected in the cecal contents, sera and livers from conventionally-raised mice but cannot be detected in germ-free mice. Pathogen-produced C4-HSL is detected in the cecal contents and sera of Citrobacter rodentium (C. rodentium)-infected mice, but not found in uninfected controls. Moreover, C. rodentium infection significantly increases the level of multiple AHL molecules in sera. Our findings demonstrate that both commensal and pathogenic bacteria, can produce AHLs that can be detected in host bodies, suggesting that quorum-sensing molecules could be a group of signaling molecules in trans-kingdom microbiota-host crosstalk.

最近的研究表明，群体感应分子可能在肠道微生物群与宿主的串扰中发挥作用。然而，微生物群是否产生群体感应分子以及这些分子是否可以跨界转运到宿主仍是未知数。在这里，我们开发了一种基于 UPLC-MS/MS 的检测方法来筛选肠道微生物群和宿主中的 27 种 N-酰基高丝氨酸内酯 (AHL)。各种 AHL 分子仅在常规饲养小鼠的盲肠内容物、血清和肝脏中检测到，但在无菌小鼠中无法检测到。在柠檬酸杆菌( C.rodentium ) 感染的小鼠的盲肠内容物和血清中检测到病原体产生的 C4-HSL ，但未在未感染的对照中发现。此外，C.rodentium感染显着增加了血清中多种 AHL 分子的水平。我们的研究结果表明，共生细菌和致病细菌都可以产生可在宿主体内检测到的 AHL，这表明群体感应分子可能是跨界微生物群与宿主串扰中的一组信号分子。