Fig. 2
From: Metabolic network of the gut microbiota in inflammatory bowel disease
The role of host-microbe interaction in expanding pathobionts and pathogens during gut inflammation. Gut inflammation changes the host epithelial metabolism, which provides nutrients and electron acceptors for the expansion of pathobionts and pathogens. Pathobionts and pathogens also utilize unique mucosal nutrients, such as ethanolamine and propanediol, that commensals cannot use for growth. In the inflamed gut, AIEC up-regulates L-serine metabolism and operates diet-derived L-serine for competitive fitness with commensal E. coli