美国斯坦福大学Michael A. Fischbach课题组发现，菌种退出揭示支配肠道微生物组代谢输出的相互作用。相关论文于2023年6月22日发表在《细胞》杂志上。
研究人员通过构建一个复杂的定义群体的变体来解决了这个问题，在这其中研究人员消除了占据胆汁酸7α-脱羟基利基的菌株。去除Clostridium scindens（Cs）和Clostridium hylemonae（Ch）消除了次级胆汁酸生产，并以高度特异的方式重塑群落：八个菌株的相对丰度变化超过100倍。在单一菌株退出的群落中，Cs和Ch达到相同的相对丰度，并以类似的程度脱羟胆汁酸。然而，孢子梭菌在ΔCs中增加了>1000倍，而在ΔCh中没有增加，进而重塑了微生物体衍生的苯丙氨酸代谢物库。因此，在一个生态位内功能多余的菌株可以在生态位外产生广泛的影响，菌株交换可以以不可预测的方式在群落中产生影响，从而对无关的群落水平表型产生巨大影响。
据悉，肠道微生物组是复杂的，从而提出了关于个体菌株在群体中的作用的问题。
附：英文原文
Title: Strain dropouts reveal interactions that govern the metabolic output of the gut microbiome
Author: Min Wang, Lucas J. Osborn, Sunit Jain, Xiandong Meng, Allison Weakley, Jia Yan, William J. Massey, Venkateshwari Varadharajan, Anthony Horak, Rakhee Banerjee, Daniela S. Allende, E. Ricky Chan, Adeline M. Hajjar, Zeneng Wang, Alejandra Dimas, Aishan Zhao, Kazuki Nagashima, Alice G. Cheng, Steven Higginbottom, Stanley L. Hazen, J. Mark Brown, Michael A. Fischbach
Issue&Volume: 2023/06/22
Abstract: The gut microbiome is complex, raising questions about the role of individual strainsin the community. Here, we address this question by constructing variants of a complexdefined community in which we eliminate strains that occupy the bile acid 7α-dehydroxylationniche. Omitting Clostridium scindens (Cs) and Clostridium hylemonae (Ch) eliminates secondary bile acid production and reshapes the community in a highlyspecific manner: eight strains change in relative abundance by >100-fold. In single-straindropout communities, Cs and Ch reach the same relative abundance and dehydroxylate bile acids to a similar extent.However, Clostridium sporogenes increases >1,000-fold in the ΔCs but not ΔCh dropout, reshaping the pool of microbiome-derived phenylalanine metabolites. Thus,strains that are functionally redundant within a niche can have widely varying impactsoutside the niche, and a strain swap can ripple through the community in an unpredictablemanner, resulting in a large impact on an unrelated community-level phenotype.
DOI: 10.1016/j.cell.2023.05.037
Source: https://www.cell.com/cell/fulltext/S0092-8674(23)00589-5