Fig. 1
From: Gut microbiota and the human gut physiological changes
Physiological factors influencing gut microbes and its immediate consequences. Enterobacteriaceae mediate sialic acid from MUC2 (main O-glycosylated product of or mcin genes) from cecal sialidase activity, which can uptake the sialic acid from synthesis of lipooligosaccharides and bacterial capsule. A regulated sIgA in normal healthy host can ensure and maintain a beneficial diverse microbiota in the gut. The binding of sIgA to the luminal bacteria support association of mucin layer and formation of biofilm, and prevent bacteria from direct access to the surface of intestinal epithelial cells