Glycan-degrading carbohydrate-active enzymes (CAZymes) / CAZy

CAZymes are enzymes responsible for the breakdown, modification or synthesis of glycoconjugates, oligosaccharides and Plant Polysaccharides / Dietary Fibers (DF) / Plant Glycans
Wolter et al. 2021 Nat Rev Gastroenterol Hepatol 18(12): 885-902

Changing exposure to antibiotics and infectious diseases could also be drivers of Glycan-Degrading Carbohydrate-Active Enzymes (CAZymes) / CAZy changes
Wolter et al. 2021 Nat Rev Gastroenterol Hepatol 18(12): 885-902

Hunter-gatherer communities and individuals in industrialized societies differ in microbial functional capacity, such as the abundance of genes encoding microbial carbohydrate-active enzymes (CAZymes)
Kaoutari et al. 2013 Nat. Rev. Microbiol. 11: 497-504
Smits et al. 2017 Science 357: 802-806

The presence of the genes for Glycan-Degrading Carbohydrate-Active Enzymes (CAZymes) / CAZy is often species- and indeed strain-specific and has been described in Bifidobacterium breve, Bifidobacterium bifidum, Bifidobacterium longum, Bifidobacterium infantis, and more rarely in Bifidobacterium pseudocatenulatum
Sela et al. 2008 Proc. Natl. Acad. Sci. U.S.A. 105: 18964-18969
Garrido et al. 2016

The ability to utilize complex dietary and host glycans is central to the survival of prominent members of the gut microbiota
Kaoutari et al. 2013 Nat. Rev. Microbiol. 11: 497-504

CAZymes encoded by the human gut microbiome catalyse the breakdown of glycoconjugates, oligosaccharides and polysaccharides to fermentable monosaccharide
Kaoutari et al. 2013 Nat. Rev. Microbiol. 11: 497-504

Glycan-Degrading Carbohydrate-Active Enzymes (CAZymes) / CAZy breakdown Microbiota-accessible carbohydrates (MACs) into fermentable monosaccharides
Kaoutari et al. 2013 Nat. Rev. Microbiol. 11: 497-504

The assembled mini-microbiome (= 177 human gut microbiota genomes) contains 15,882 different Glycan-degrading carbohydrate-active enzymes (CAZymes) / CAZy genes distributed unequally between glycosyltransferase, carbohydrate esterase, Glycoside hydrolases (GHs) and Polysaccharide lyases (PLs) genes
Kaoutari et al. 2013 Nat. Rev. Microbiol. 11: 497-504

The phyla with 86% of the GH and PL genes are Firmicutes and Bacteroidetes. These genes are lower by a factor of 10 in the phyla Actinobacteria and Proteobacteria
Kaoutari et al. 2013 Nat. Rev. Microbiol. 11: 497-504

The human genome encodes a limited number of glycoside hydrolases and no Polysaccharide lyases (PLs) (collectively referred to as carbohydrate-active enzymes, or Glycan-degrading carbohydrate-active enzymes (CAZymes) / CAZy)
Cantarel et al. 2012 PLOS One 7: e28742

There are two types of enzyme that cleave glycosidic bonds between carbohydrates or between a carbohydrate and a non-carbohydrate moiety: Glycoside hydrolases (GHs), which cleave bonds by the insertion of a water molecule (hydrolysis), and Polysaccharide lyases (PLs), which cleave complex carbohydrates using an elimination mechanism
Henrissat 1991 Biochem. J. 280: 309-316
Lombard et al. 2010 Biochem. J. 432: 437-444
Koropatkin et al. 2012 Nature Rev. Microbiol. 10: 323-335

The CAZy database lists two additional categories of Glycan-degrading carbohydrate-active enzymes (CAZymes) / CAZy, namely Carbohydrate esterases, which remove ester substituents from the glycan chains to facilitate the action of Glycoside hydrolases (GHs) and Polysaccharide lyases (PLs), and glycosyltransferases, which assemble complex carbohydrates from activated sugar donors
Lairson et al. 2008 Annu. Rev. Biochem. 77: 521-555

see also:
Bifidobacterium / Bifidobacter & Human Milk Oligosaccharides (HMOs)
Carbohydrate fermentation
Digestion
Digestion & Gut microbiota
Genome & Gut microbiota
Gut microbiota & Physical well-being / Health
Intestinal Epithelial Barrier / Mucosal Barrier / Mucus Layer