Speaker
Description
Authors: Svenja Busche, Danielle Harris, Konrad Aden, Silvio Waschina
Auxotrophies are defined by the incapability of an organism to synthesize essential nutrients resulting in a dependence on the nutritional environment. Amino acids are vital nutrients for the human host and auxotrophic bacteria within the gut microbiome, which could result in competition for specific amino acids. However, the prevalence of bacterial auxotrophies and the impact on host physiology remains obscure. Here, we applied genome-scale metabolic modelling to predict amino acid auxotrophies in 3652 common human gut bacteria and evaluated statistically the influence of auxotrophies on the metabolic profile. Furthermore, the frequency of auxotrophies was estimated based on microbiome data from a large population cohort study and statistically tested for associations with health parameters and metabolome data. Among all proteinogenic amino acids, tryptophan auxotrophies were predicted to have the highest abundance in the human gut microbiome. Overall, auxotrophies for amino acids essential to the host are abundant in the gut microbiome. Branched-chain amino acid auxotrophic bacteria were more prone to produce lactate. Further, the data analysis revealed the distribution of auxotrophies as a major determinant of the stool metabolome in chronic inflammatory diseases. In short, the results show that auxotrophic bacteria are common in the human gut microbiome and indicate a potential influence on human health.
