Abstract：
Earthworms can redistribute soil microbiota, and thus might affect the profile of virulence factor genes (VFGs) which are carried by pathogens in soils. Nevertheless, the knowledge of VFG profile in the earthworm guts and its interaction with earthworm gut microbiome is still lacking. Herein, we characterized earthworm gut and soil microbiome and VFG profiles in natural and agricultural ecosystems at a national scale using metagenomics. VFG profiles in the earthworm guts significantly differed from those in the surrounding soils, which was mainly driven by variations of bacterial communities. Furthermore, the total abundance of different types of VFGs in the earthworm guts was about 20-fold lower than that in the soils due to the dramatic decline (also by approximately 20-fold) of VFG-carrying bacterial pathogens in the earthworm guts. Additionally, five VFGs related to nutritional/metabolic factors and stress survival were identified as keystones merely in the microbe-VFG network in the earthworm guts, implying their pivotal roles in facilitating pathogen colonization in earthworm gut microhabitats. These findings suggest the potential roles of earthworms in reducing risks related to the presence of VFGs in soils, providing novel insights into earthworm-based bioremediation of VFG contamination in terrestrial ecosystems.
摘要：
蚯蚓可以重新分配土壤微生物群，因此可能会影响土壤中病原体携带的毒力因子基因（VFG）的概况。然而，仍然缺乏对蚯蚓肠道VFG谱及其与蚯蚓肠道微生物组相互作用的认识。在这里，我们使用宏基因组学在全国范围内表征了自然和农业生态系统中的蚯蚓肠道和土壤微生物组和VFG谱。蚯蚓内脏中的VFG剖面与周围土壤中的VFG剖面明显不同，这主要是由细菌群落的变化驱动的。此外，蚯蚓肠道中不同类型的VFG的总丰度比土壤低约20倍，这是由于蚯蚓肠道中携带VFG的细菌病原体急剧下降（也下降了约20倍）。此外,与营养/代谢因素和压力生存有关的五个VFG仅在earth肠道中的微生物-VFG网络中被确定为基石，暗示它们在促进病原体在蚯蚓肠道微生境中定植方面的关键作用。这些发现表明，蚯蚓在降低与土壤中VFGs存在相关的风险方面的潜在作用。为基于蚯蚓的陆地生态系统VFG污染生物修复提供新的见解。
