华盛顿大学医学院Jeffrey I. Gordon小组的最新研究揭示，物种间的竞争影响纤维聚糖从而对人类肠道细菌进行靶向调控。2019年9月19日出版的《细胞》杂志刊登了这一结果。
研究人员将无菌小鼠定殖来着人体肠道的细菌菌株集合体，并喂食34种纤维不同的食物组合，这些纤维是美国代表性低纤维饮食食品中所含有的。使用针对群落菌群基因表达的定量蛋白质组学分析结合前向遗传筛选的方法鉴定了靶向类杆菌属物种纤维制剂中的生物活性化合物。人为控制群落个体数量与可检测的人造食物颗粒使用相结合的方法，揭示了目标物种对纤维降解的贡献；这些人造食物颗粒由膳食多糖包裹的顺磁性微观珠粒组成。研究者使用不同方法，包括基于珠子的生物传感器，确定了营养吸收的策略，这些策略决定并缓解了拟杆菌之间的竞争并控制了MDF组分的选择性。
据悉，微生物定向食物（MDF）是可以选择性地增加有益的人肠道微生物丰度及其表达功能的食品，MDF的研发需要知道MDF的生物活性成分和微生物-微生物相互作用的机制。
附：英文原文
Title: Interspecies Competition Impacts Targeted Manipulation of Human Gut Bacteria by Fiber-Derived Glycans
Author: Michael L. Patnode, Zachary W. Beller, Nathan D. Han, Jiye Cheng, Samantha L. Peters, Nicolas Terrapon, Bernard Henrissat, Sophie Le Gall, Luc Saulnier, David K. Hayashi, Alexandra Meynier, Sophie Vinoy, Richard J. Giannone, Robert L. Hettich, Jeffrey I. Gordon
Issue&Volume: Volume 179 Issue 1
Summary:
Development of microbiota-directed foods (MDFs) that selectively increase the abundance of beneficial human gut microbes, and their expressed functions, requires knowledge of both the bioactive components of MDFs and the mechanisms underlying microbe-microbe interactions. Here, gnotobiotic mice were colonized with a defined consortium of human-gut-derived bacterial strains and fed different combinations of 34 food-grade fibers added to a representative low-fiber diet consumed in the United States. Bioactive carbohydrates in fiber preparations targeting particular Bacteroides species were identified using community-wide quantitative proteomic analyses of bacterial gene expression coupled with forward genetic screens. Deliberate manipulation of community membership combined with administration of retrievable artificial food particles, consisting of paramagnetic microscopic beads coated with dietary polysaccharides, disclosed the contributions of targeted species to fiber degradation. Our approach, including the use of bead-based biosensors, defines nutrient-harvesting strategies that underlie, as well as alleviate, competition between Bacteroides and control the selectivity of MDF components.
DOI: 10.1016/j.cell.2019.08.011
Source: https://www.cell.com/cell/fulltext/S0092-8674(19)30899-2