Gut microbiota ecosystem (Clostridioides difficile colonization resistance)

The gut microbiota ecosystem represents the diverse community of microorganisms in the human intestine that maintains a state of colonization resistance against opportunistic pathogens (Buffie et al., 2015, Nature). In healthy individuals, commensal bacteria prevent the expansion of Clostridioides difficile by competing for limited nutrients and converting primary bile acids into secondary bile acids, which inhibit C. difficile spore germination and vegetative growth (Sorg & Sonenshein, 2008, Journal of Bacteriology). When antibiotics disrupt this ecological balance, a state of dysbiosis occurs, allowing C. difficile to proliferate and produce toxins (TcdA and TcdB) that cause mucosal inflammation and diarrhea (CDC, 2023). Therapeutic strategies like Fecal Microbiota Transplantation (FMT) and FDA-approved live biotherapeutic products, such as Vowst and Rebyota, aim to restore the microbial diversity and metabolic functions of the ecosystem (FDA, 2023). These interventions re-establish the inhibitory environment, effectively preventing recurrent infections by filling the vacant ecological niches and restoring metabolic signaling (Khanna et al., 2022, JAMA).

Other names

Gut microbiomeIntestinal floraColonization resistanceC. difficile colonization

Restoration of colonization resistance through competitive exclusion, nutrient competition, and production of inhibitory metabolites like secondary bile acids.