Laboratory of Gastrointestinal Microbiology, Nanjing Agricultural University, Nanjing 210095, China.
Front Biosci (Landmark Ed). 2011 Jan 1;16(5):1768-86. doi: 10.2741/3820.
Bacteria in the gastrointestinal (GI) tract play an important role in the metabolism of dietary substances in the gut and extraintestinal tissues. Amino acids (AA) should be taken into consideration in the development of new strategies to enhance efficiency of nutrient utilization because they are not only major components in the diet and building blocks for protein but also regulate energy and protein homeostasis in organisms. The diversity of the AA-fermenting bacteria and their metabolic redundancy make them easier to survive and interact with their neighboring species or eukaryotic host during transition along GI tract. The outcomes of the interactions have important impacts on gut health and whole-body homeostasis. The AA-derived molecules produced by intestinal bacteria affect host health by regulating either host immunity and cell function or microbial composition and metabolism. Emerging evidence shows that dietary factors, such as protein, non-digestible carbohydrates, probiotics, synbiotics and phytochemicals, modulate AA utilization by gut microorganisms. Interdisciplinary research involving nutritionists and microbiologists is expected to rapidly expand knowledge about crucial roles for AA in gut ecology and host health.
胃肠道（GI）中的细菌在肠道和肠道外组织中对膳食物质的代谢起着重要作用。在开发提高营养利用效率的新策略时，应该考虑氨基酸（AA），因为它们不仅是饮食中的主要成分和蛋白质的构建块，而且还调节生物体中的能量和蛋白质稳态。AA 发酵细菌的多样性及其代谢冗余使它们在沿着胃肠道的过渡过程中更容易生存并与邻近物种或真核宿主相互作用。相互作用的结果对肠道健康和全身稳态有重要影响。肠道细菌产生的 AA 衍生分子通过调节宿主免疫和细胞功能或微生物组成和代谢来影响宿主健康。新出现的证据表明，膳食因素，如蛋白质、不可消化的碳水化合物、益生菌、合生元和植物化学物质，可调节肠道微生物对 AA 的利用。涉及营养学家和微生物学家的跨学科研究有望迅速扩大对 AA 在肠道生态和宿主健康中关键作用的认识。
