Background: Streptococcus thermophilus is one of the most prevalent species in stool samples of westernized populations due to continuous exposure to fermented dairy products. However, few studies have explored alterations in fecal and serum metabolites in hosts by multiple S. thermophilus strains. In the present study, we investigated how four S. thermophilus strains influenced the gut microbiota and host metabolism after 28 days of intervention in mice.Results: The results indicate that the consumption of S. thermophilus affected the host with strain specificity. Tryptophan metabolism is regulated by decreased indole derivatives and increased serotonin generation by the four S. thermophilus strains, which is mainly related to the reduction of Alistipes and Eubacterium. Ingestion of strains DYNDL13-4 and DQHXNQ38M61 resulted in more remarkable changes in amino acid metabolism and lipid metabolism than that of strains LMD9 and 4M6, which may be related to the elevation of intestinal Bifidobacterium by DYNDL13-4 and DQHXNQ38M61. Comparative genomic analysis revealed that the four S. thermophilus strains belonged to different branches in the phylogenetic tree, and DYNDL13-4 and DQHXNQ38M61 had more genes involved in carbohydrate metabolism, amino acid metabolism, membrane transport, and signal transduction.Conclusions: Our study provides valuable information for understanding the regulation of host metabolism after consuming different S. thermophilus strains and could facilitate potential personalized applications of S. thermophilus based on strain varieties.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.