Center for Microbial Ecology and Technology, Ghent University, Coupure Links 653, 9000 Ghent, Belgium.
Laboratory of Molecular Bacteriology, Department of Microbiology and Immunology, KU Leuven, Herestraat 49, 3000 Leuven, Belgium.
FEMS Microbiol Ecol. 2021 Aug 17;97(9). doi: 10.1093/femsec/fiab111.
A recently introduced quantitative framework for gut microbiota analysis indicated that microbial load alterations can be linked to various diseases, making it essential to pinpoint its determinants. We identified nutrient load as a main driver of the quantitative microbial community composition and functionality in vitro by stepwise decreasing standardized feed concentrations from 100% to 33%, 20% and 10% in 5-day intervals. While the proportional composition and metabolic profile were mainly determined by the inter-individual variability (35% and 41%), nutrient load accounted for 58%, 23% and 65% of the observed variation in the microbial load, quantitative composition and net daily metabolite production, respectively. After the 10-fold nutrient reduction, the microbial load decreased by 79.72 ± 9% and 82.96 ± 1.66% in the proximal and distal colon, respectively, while the net total short-chain fatty acid production dropped by 79.42 ± 4.42% and 84.58 ± 2.42%, respectively. The majority of microbial taxa quantitatively decreased, whereas a select group of nutritional specialists, such as Akkermansia muciniphila and Bilophila wadsworthia, and a number of opportunistic pathogens remained unaffected. This shows that nutrient load is an important driver of the human gut microbiome and should be considered in future in vitro and in vivo dietary research.
最近引入的一种定量肠道微生物组分析框架表明，微生物负荷的改变可能与各种疾病有关，因此确定其决定因素至关重要。我们通过逐步将标准化饲料浓度从 100%降低至 33%、20%和 10%，每 5 天间隔一次，在体外确定了营养负荷是微生物群落组成和功能定量变化的主要驱动因素。虽然比例组成和代谢特征主要由个体间的变异性决定（分别占 35%和 41%），但营养负荷分别占微生物负荷、定量组成和净日代谢产物产生的观察到的变异性的 58%、23%和 65%。在营养物质减少 10 倍后，近端和远端结肠的微生物负荷分别减少了 79.72±9%和 82.96±1.66%，而净总短链脂肪酸的产生分别减少了 79.42±4.42%和 84.58±2.42%。大多数微生物类群在数量上减少，而少数营养专性菌，如 Akkermansia muciniphila 和 Bilophila wadsworthia，以及一些机会性病原体不受影响。这表明营养负荷是人类肠道微生物组的重要驱动因素，在未来的体外和体内饮食研究中应予以考虑。
