Compositional and functional features of the gastrointestinal microbiome and their effects on human health

Abstract

The human gastrointestinal tract contains distinct microbial communities that differ in composition and function based on their location, as well as age, sex, race/ethnicity, and diet of their host. We describe the bacterial taxa present in different locations of the GI tract, and their specific metabolic features. The distinct features of these specific microbial communities might affect human health and disease. Several bacterial taxa and metabolic modules (biochemical functions) have been associated with human health and the absence of disease. Core features of the healthy microbiome might be defined and targeted to prevent disease and optimize human health.

Keywords: Gastrointestinal; HMP; Lumen; Metagenomics; Microbe; Mucosa.

Figure 1. The Intestinal Microbiome and its Effects in the Intestinal Mucosa

The intestinal microbiome (top) lies adjacent to the intestinal epithelium. Specific effects are described in text boxes.

Figure 2. Immunomodulation by the Intestinal Microbiome

Microbial metabolites regulate the mucosal immune system in the intestine through pro-inflammatory and antiinflammatory mechanisms. Immunostimulation can occur in response to the release of proinflammatory cytokines from epithelial cells, mononuclear cells, and lymphocytes, antiinflammatory responses are driven by the production of TGF-β and IL-10 from epithelial and mononuclear cells. Reprinted from (69).