Carbohydrate metabolism & Gut microbiota

Dietary fiber that is indigestible for host enzymes is an essential Energy source for gut symbionts
Cummings & Macfarlane 1991 Journal of Applied Bacteriology 70: 443-459
Lee et al. 2022 Journal of Microbiology 60(2) 215-223

Changes in the composition of dietary polysaccharides lead to altered expression of bacterial carbohydrate-degrading enzymes
Sonnenburg et al. 2005 Science 307: 1955
Desai et al. 2016 Cell 167: 1339–1353
Lee et al. 2022 Journal of Microbiology 60(2) 215-223

Carbohydrate utilization has been extensively investigated in the prominent human symbiont, Bacteroides thetaiotaomicron
Lee et al. 2022 Journal of Microbiology 60(2) 215-223

The mammalian system is majorly dependent on the colonic microbiota for the degradation of complex carbohydrates (Plant Polysaccharides )
Stephen-Victor et al. 2020 Immunity 53(2): 277-289

Microbes compete or cooperate to uptake essential nutrients, mainly carbohydrates. Studies on Bacteroides thetaiotaomicron have uncovered complex transcriptional and post-transcriptional control networks that help adjust bacterial gene expression in response to carbon availability
Schwalm & Groisman 2017 Trends Microbiol 25: 1005-1015
Wexler & Goodman 2017 Nat Microbiol 2: 17026
Ryan et al. 2020a Biol Chem 402: 55-72

For example, in comparison to the human genome, Bacteroides thetaiotaomicron alone comprises of more than 170 polysaccharide degrading enzymes
Cantarel et al. 2012 PLOS One 7: e28742
Xu et al. 2003 Science 299: 2074
Stephen-Victor et al. 2020 Immunity 53(2): 277-289

Increasing the proportion of Lactobacilli and Bifidobacteria with prebiotics increase circulating gut peptides such as glucagon-like peptide-1 (GLP-1) and peptide YY (PYY), which benefit metabolism
Delmée et al. 2006 Life Sci. 79: 1007–1013
Overduin et al. 2013 Br. J. Nutr. 31: 1–11

see also:
Bacteroides thetaiotaomicron & Fiber-Degrading
Polysaccharide utilization loci (PULs)