Please join us for the Food for Health Seminar Series.

Dr. Eric Martens will present, “Degradation of diet and host derived polysaccharides by human gut bacteria: roles in health and disease”.

Seminar Time: Noon- 1pm CST

Zoom Information:
Zoom URL-> https://unl.zoom.us/j/310580348?pwd=RWZ1K2diNVJNbWNtS1VQWWhpRzAzUT09

Zoom Password: NFHC

Or Join by Telephone: Dial- US: +1 346 248 7799 or +1 669 900 6833

Meeting ID: 310 580 348

Abstract: Colonic bacteria are responsible for nearly all of human dietary fiber digestion. Despite the accepted health benefits of consuming dietary fiber, little is known about the precise mechanisms by which fiber levels impact the gut microbiota and alter disease risk or how the precise chemistry of fiber polysaccharides interfaces with the hundreds of gut microbiota species. Using gnotobiotic mouse models, functional genomics, biochemical and genetic studies we have explored these interactions in mechanistic depth. One of the prominent groups of human gut bacteria (Bacteroidetes) deploy their armament of fiber-degrading enzymes in genomically linked “polysaccharide utilization loci” (PULs). Work in my lab, or by others, has identified PULs for degradation of nearly all known terrestrial fiber polysaccharides and secreted host glycans. In recent studies in which animals were colonized with a synthetic human gut microbiota composed of fully sequenced commensal bacteria, we have elucidated the functional interactions between dietary fiber, the gut microbiota and the colonic mucus barrier, which serves as a primary defense against enteric pathogens. During chronic or intermittent dietary fiber deficiency, the gut microbiota resorts to host-secreted mucus glycoproteins as a nutrient source, leading to erosion of the colonic mucus barrier. Dietary fiber deprivation, together with a fiber-deprived, mucus-eroding microbiota, promotes inflammatory disease in the absence of overt pathogens in IL-10-deficient mice. Our work has begun to unravel the intricate pathways linking diet, the gut microbiome and intestinal barrier dysfunction, which could be exploited to improve health using dietary fiber or prebiotic therapeutics.

Please reach out to Allie Claypool with any questions.