A review of the relationship between the gut microbiota and amino acid metabolism

Abstract

New evidence has emerged in recent years to suggest a strong link between the human gut microbiota, its metabolites, and various physiological aspects of hosts along with important pathophysiological dimensions of diseases. The research indicates that the gut microbiota can facilitate metabolite production in two ways: first, the resident species of the gut microbiota use the amino acids produced from food or the host as elements for protein synthesis, and second, conversion or fermentation are used to drive nutrient metabolism. Additionally, the gut microbiota can synthesize several nutritionally essential amino acids de novo, which is a potential regulatory factor in amino acid homeostasis. The primary objective of this review is to summarize the current literature relating to the ways in which microbial amino acids contribute to host amino acid homeostasis.

Obesity Impairs Oligopeptide/Amino Acid‐Induced Ghrelin Release and Smooth Muscle Contractions in the Human Proximal Stomach

“…AA TASRs were also expressed in mouse colonic strips and suggest a role for AAs, either produced from the food or generated de novo, by the gut microbiota in colonic contractility. [48] AA-induced SM contractions were mediated by the CaSR and dependent upon extracellular Ca 2+ . The functional role of the umami receptor could not be elucidated since lactisole is specific for human TAS1R1-TAS1R3.…”

“…The effect of oligopeptide/AAs on contractility in the human fundus is mimicked in mice. AA TASRs were also expressed in mouse colonic strips and suggest a role for AAs, either produced from the food or generated de novo, by the gut microbiota in colonic contractility . AA‐induced SM contractions were mediated by the CaSR and dependent upon extracellular Ca 2+ .…”

Nutritional Status as a Mediator of Fatigue and Its Underlying Mechanisms in Older People

“…Additionally, fast digested proteins seem to better stimulate muscle protein accretion, even if results should be confirmed in larger trials [113]. Some proteins are metabolized to short chain fatty acids (i.e., propionate, butyrate and acetate) which are used by muscle cells to produce energy [116][117][118][119]. Short chain fatty acids also promote muscle anabolism and display anti-inflammatory proprieties [120][121][122][123].…”

Metabolism at the centre of the host–microbe relationship

“…Amino acid metabolism is regulated by the gut microbiota, which affects the amount and type of amino acids available to the host [48][49][50]. Tryptophan is an essential amino acid important for the generation of a range of bioactive molecules, including serotonin and melatonin [51].…”