Heparinase III: Proteins and Enzymes

Heparan sulfate is a sulfated glycosaminoglycan with the repeating disaccharide units of -4HexA1,4GlcNAc beta1-. It is usually attached to the protein cores of proteoglycans found on the cell membrane and in the extracellular matrix where it binds to a variety of protein ligands and regulates a wide range of biological activities. Heparan sulfate has a domain structure where sulfated regions are interspaced with less or non-sulfated regions. Heparin shares the backbone structure with heparan sulfate but contains no non-sulfated regions. Heparinases are a family of lyases that release unsaturated oligosaccharides from heparin and heparan sulfate upon digestion. Heparinase I recognizes highly sulfated regions and is more specific for heparin. Heparinase II digests both heparin and heparan sulfate. Heparinase III prefers less-sulfated regions and is more active on heparan sulfate.