Sequencing Heparan Sulfate Saccharides
The functions of the heparan sulfates (HSs) are determined by specific saccharide motifs within HS chains. These sequences confer selective protein binding properties and the ability to modulate protein activities (1,2). HS chains consist of an alternating disaccharide repeat of glucosamine (GlcN; N-acetylated or N-sulfated) and uronic acid (glucuronic [GlcA] or iduronic acid [IdoA]). The initial biosynthetic product containing N-acetylglucosamine (GlcNAc) and GlcA is modified by N-sulfation of the GlcN, ester (O)-sulfation (at positions 3 and 6 on the GlcN and position 2 on the uronic acids) and by epimerization of GlcA to IdoA. The extent of these modifications is incomplete and their degree and distribution varies in HS between different cell types. In HS chains N- and O-sulfated sugars are predominantly clustered in sequences of up to eight disaccharide units separated by N-acetyl-rich regions with relatively low sulfate content (3).
KeywordsUronic Acid Ammonium Persulfate Electrophoresis Buffer Sodium Cyanoborohydride Hexuronic Acid
- 10.Hopwood, J. (1989) Enzymes that degrade heparin and heparan sulfate, in Heparin (Lane and Lindahl, eds.), Edward Arnold Press, pp. 191–227.Google Scholar