Department of Ecology and Evolutionary Biology, Yale University, 165 Prospect St., New Haven, CT, 06511, USA.
Department of Biology, University of Florida, Gainesville, FL, USA.
Sci Rep. 2021 Nov 30;11(1):23117. doi: 10.1038/s41598-021-02349-1.
All animals carry specialized microbiomes, and their gut microbiota are continuously released into the environment through excretion of waste. Here we propose the meta-gut as a novel conceptual framework that addresses the ability of the gut microbiome released from an animal to function outside the host and alter biogeochemical processes mediated by microbes. We demonstrate this dynamic in the hippopotamus (hippo) and the pools they inhabit. We used natural field gradients and experimental approaches to examine fecal and pool water microbial communities and aquatic biogeochemistry across a range of hippo inputs. Sequencing using 16S RNA methods revealed community coalescence between hippo gut microbiomes and the active microbial communities in hippo pools that received high inputs of hippo feces. The shared microbiome between the hippo gut and the waters into which they excrete constitutes a meta-gut system that could influence the biogeochemistry of recipient ecosystems and provide a reservoir of gut microbiomes that could influence other hosts. We propose that meta-gut dynamics may also occur where other animal species congregate in high densities, particularly in aquatic environments.
所有动物都携带有特定的微生物组，其肠道微生物组通过排泄废物不断释放到环境中。在这里，我们提出了元肠道的新概念框架，以解决从动物体内释放的肠道微生物组在宿主外发挥功能并改变微生物介导的生物地球化学过程的能力。我们在河马（hippo）及其栖息的水池中证明了这一动态。我们利用自然野外梯度和实验方法，研究了一系列河马输入下粪便和水池水微生物群落和水生生物地球化学。使用 16S RNA 方法进行测序揭示了河马肠道微生物组与接受大量河马粪便输入的河马水池中活跃微生物群落之间的群落融合。河马肠道和排泄到其中的水之间的共享微生物组构成了一个元肠道系统，可能会影响受纳生态系统的生物地球化学，并提供可能影响其他宿主的肠道微生物组的储库。我们提出，元肠道动态也可能发生在其他动物物种高密度聚集的地方，特别是在水生环境中。
