Antibiotic-Sensitive Gut Symbiont Turicibacter sanguinis Alleviates Constipation by Enhancing Short-chain Fatty Acids and Tryptophan Metabolism

Turicibacter sanguinis (T. sanguinis) is a prominent genus within the mammalian gut microbiota and is associated with various metabolic and gastrointestinal disorders, including overweight, obesity, irritable bowel syndrome (IBS) and constipation. However, the specific roles of T. sanguinis in host physiology remain unclear. In this study, antibiotic intervention experiments in mice revealed that T. sanguinis abundance was significantly reduced by intervention with sisomicin sulfate, ribostamycin sulfate, and cefadroxil, providing a T. sanguinis-depleted model for further investigations. By analyzing 6040 gut metagenomes, we observed an enrichment of T. sanguinis in IBS patients, while its abundance was significantly decreased in individuals with constipation. Next, using a T. sanguinis-depleted mouse model, we further validated the functional role of T. sanguinis in alleviating loperamide-induced constipation. Analysis of short-chain fatty acid (SCFA) and metabolomics revealed that T. sanguinis supplementation increased the levels of butyrate and isobutyrate in the colon and enhanced tryptophan metabolism, particularly elevating 5-hydroxytryptamine (5-HT) levels in intestinal tissue. Together, our findings identify T. sanguinis as a microbial mediator in antibiotic-associated constipation and offer new insights into microbiota-targeted therapies for functional gastrointestinal disorders.