heparin proteoglycan biosynthetic process
heparin proteoglycan biosynthetic process
The chemical reactions and pathways resulting in the formation of heparin proteoglycans, which consist of a core protein linked to a heparin glycosaminoglycan. The heparin chain is composed of the repeating disaccharide unit beta-(1,4)-N-acetyl-D-glucosamine-alpha-(1,4)-hexuronic acid, the former being either sulfated or deacetylated on its amino group as well as sulfated on one of its hydroxyl groups, and the latter being a mixture of sulfated and nonsulfated D-glucuronic and L-iduronic acids. Heparin is similar to heparan sulfate but it contains more N-sulfate and O-sulfate groups. Heparin chains are covalently linked to serine/threonine residues (O-linked) of the core protein via a tetrasaccharide linker sequence (xylose-galactose-galactose-glucuronate).