Microbial diversity

Microbial diversity refers to the variety and relative abundance of different microorganisms within a specific environment, most notably the human gastrointestinal tract. In a healthy state, high microbial diversity is associated with resilience and the performance of essential biological functions, including the fermentation of dietary fibers into short-chain fatty acids and the training of the host immune system (NIH, 2022). A significant loss in diversity, often termed dysbiosis, is a hallmark of various pathological conditions such as recurrent Clostridioides difficile infection (CDI) and inflammatory bowel disease (IBD) (MDPI, 2022). Therapeutic strategies, such as fecal microbiota transplantation (FMT) and refined consortium-based drugs like SER-109 (Vowst), aim to restore this diversity to re-establish 'colonization resistance'—the ability of a diverse microbial community to prevent the overgrowth of opportunistic pathogens (PMC, 2021). While not a single molecular target like a receptor or enzyme, microbial diversity serves as a systemic therapeutic objective and a critical biomarker for the efficacy of microbiome-based interventions. Recent FDA approvals of standardized microbiome products highlight the clinical importance of modulating these complex ecological communities to resolve disease (Seres Therapeutics, 2022).

Other names

Microbiome diversityMicrobiota diversityAlpha diversityBeta diversityGut flora varietyEcological richnessTaxonomic diversity

Therapies restore microbial diversity to re-establish colonization resistance via competitive exclusion, production of antimicrobial metabolites, and modification of the bile acid pool to inhibit the germination and growth of pathogens.