Samuel Buck S, Gordon Jeffrey I
Center for Genome Sciences, Washington University School of Medicine, 4444 Forest Park, St. Louis, MO 63108, USA.
Proc Natl Acad Sci U S A. 2006 Jun 27;103(26):10011-6. doi: 10.1073/pnas.0602187103. Epub 2006 Jun 16.
Our colons harbor trillions of microbes including a prominent archaeon, Methanobrevibacter smithii. To examine the contributions of Archaea to digestive health, we colonized germ-free mice with Bacteroides thetaiotaomicron, an adaptive bacterial forager of the polysaccharides that we consume, with or without M. smithii or the sulfate-reducing bacterium Desulfovibrio piger. Whole-genome transcriptional profiling of B. thetaiotaomicron, combined with mass spectrometry, revealed that, unlike D. piger, M. smithii directs B. thetaiotaomicron to focus on fermentation of dietary fructans to acetate, whereas B. thetaiotaomicron-derived formate is used by M. smithii for methanogenesis. B. thetaiotaomicron-M. smithii cocolonization produces a significant increase in host adiposity compared with monoassociated, or B. thetaiotaomicron-D. piger biassociated, animals. These findings demonstrate a link between this archaeon, prioritized bacterial utilization of polysaccharides commonly encountered in our modern diets, and host energy balance.
我们的结肠中栖息着数万亿微生物，其中包括一种重要的古菌——史氏甲烷短杆菌。为了研究古菌对消化健康的作用，我们用嗜黏蛋白阿克曼氏菌对无菌小鼠进行定殖，嗜黏蛋白阿克曼氏菌是一种可适应的细菌，以我们摄入的多糖为食，同时添加或不添加史氏甲烷短杆菌或脱硫弧菌。对嗜黏蛋白阿克曼氏菌进行全基因组转录谱分析，并结合质谱分析，结果显示，与脱硫弧菌不同，史氏甲烷短杆菌能引导嗜黏蛋白阿克曼氏菌专注于将膳食果聚糖发酵为乙酸盐，而嗜黏蛋白阿克曼氏菌产生的甲酸盐则被史氏甲烷短杆菌用于产甲烷。与单定殖或嗜黏蛋白阿克曼氏菌-脱硫弧菌双定殖的动物相比，嗜黏蛋白阿克曼氏菌-史氏甲烷短杆菌共定殖会使宿主肥胖显著增加。这些发现证明了这种古菌、现代饮食中常见多糖的优先细菌利用以及宿主能量平衡之间的联系。
