Microbial glycosaminoglycan glycosyltransferases.
Glycosaminoglycans, a class of linear polysaccharides composed of repeating disaccharide units containing a hexosamine, are important carbohydrates found in many organisms. Vertebrates utilize glycosaminoglycans in structural, recognition, adhesion, and signaling roles. Certain pathogenic bacteria produce extracellular capsules composed of glycosaminoglycans or glycosaminoglycan-like polymers that enhance the microbes' ability to infect or to colonize the host. In the period from 1993 to 2001, bacterial enzymes were discovered that catalyze the polymerization of the repeating unit of hyaluronan, chondroitin, or N-acetylheparosan (unsulfated, unepimerized heparin). Depending on the specific carbohydrate and the microorganism, either a dual-action enzyme (synthase) that transfers two distinct monosaccharides or a pair of single-action transferases are utilized to synthesize the glycosaminoglycan polymer. Current views on the enzymology, structures, potential evolution, and the roles of the known glycosyltransferases from Streptococcus, Pasteurella, and Escherichia are discussed.
DeAngelis
Paul L
PL
Department of Biochemistry and Molecular Biology, Oklahoma Center for Medical Glycobiology, University of Oklahoma Health Sciences Center, 940 Stanton L. Young Blvd., Oklahoma City, OK 73104, USA.
D001419:Bacteria / Q000201:enzymology*; D006025:Glycosaminoglycans / Q000378:metabolism*; D016695:Glycosyltransferases / Q000378:metabolism*
D006025:Glycosaminoglycans; D016695:Glycosyltransferases