The gastrointestinal tract (GIT) of humans and animals is host to a complex community of different microorganisms whose activities significantly influence host nutrition and health through enhanced metabolic capabilities, protection against pathogens, and regulation of the gastrointestinal development and immune system. New molecular technologies and concepts have revealed distinct interactions between the gut microbiota and dietary amino acids (AAs) especially in relation to AA metabolism and utilization in resident bacteria in the digestive tract, and these interactions may play significant roles in host nutrition and health as well as the efficiency of dietary AA supplementation. After the protein is digested and AAs and peptides are absorbed in the small intestine, significant levels of endogenous and exogenous nitrogenous compounds enter the large intestine through the ileocaecal junction. Once they move in the colonic lumen, these compounds are not markedly absorbed by the large intestinal mucosa, but undergo intense proteolysis by colonic microbiota leading to the release of peptides and AAs and result in the production of numerous bacterial metabolites such as ammonia, amines, short-chain fatty acids (SCFAs), branched-chain fatty acids (BCFAs), hydrogen sulfide, organic acids, and phenols. These metabolites influence various signaling pathways in epithelial cells, regulate the mucosal immune system in the host, and modulate gene expression of bacteria which results in the synthesis of enzymes associated with AA metabolism. This review aims to summarize the current literature relating to how the interactions between dietary amino acids and gut microbiota may promote host nutrition and health.

人类和动物的胃肠道（GIT）拥有多种不同微生物的复杂群落，它们的活动通过增强的代谢能力，对病原体的保护以及对胃肠道发育和免疫系统的调节，显着影响宿主的营养和健康。新的分子技术和概念揭示了肠道菌群与膳食氨基酸（AAs）之间的独特相互作用，尤其是与消化道中常驻细菌的AA代谢和利用有关，这些相互作用也可能在宿主营养和健康中发挥重要作用作为膳食AA补充的效率。消化蛋白质并将AA和肽吸收到小肠后，大量的内源性和外源性含氮化合物通过回盲肠连接进入大肠。一旦它们进入结肠腔，这些化合物就不会被大肠粘膜明显吸收，而是通过结肠微生物群进行强烈的蛋白水解，从而导致肽和AA释放，并导致产生大量细菌代谢产物，例如氨，胺，短链脂肪酸（SCFA），支链脂肪酸（BCFA），硫化氢，有机酸和酚。这些代谢物影响上皮细胞中的各种信号传导途径，调节宿主中的粘膜免疫系统，并调节细菌的基因表达，从而导致与AA代谢相关的酶的合成。