Heparan sulfate is a highly sulfated polysaccharide found on the cell surface and within the extracellular matrix. Typically, it is covalently attached to the protein core of proteoglycans, such as syndecans and glypicans. Heparin, on the other hand, can be considered as a highly sulfated version of heparan sulfate that is predominantly found in mast cells. Both heparin and heparan sulfate contain disaccharide repeats of uronic acid and Nacetylglucosamine and are modified by the same sulfotransferases (1, 2). The uronic acid residues are either glucuronic acid or iduronic acid and maybe sulfated at the 2O position by heparan sulfate 2O sulfotransferase 1 (HS2ST1) (3, 4). HS2ST1 physically interacts in the Golgi apparatus with glucuronyl c5epimerase (5), which catalyzes the conversion of glucuronic acid to iduronic acid (6). As a consequence, 2O
sulfation predominantly occurs on iduronic acids naturally and overexpression of HS2ST1 alone causes an increase in 2O sulfation on glucuronic acid (7). Our recombinant HS2ST1 was expressed in CHO cells, and the enzyme activity was assayed using an SDS-PAGE
method (8).
Source:
Recombinant corresponding to Met59-Asn356 from human HS2ST1, N-terminal, human CD33 signal sequence and 6-His tag, expressed in CHO cells.
Molecular Weight:
~36kD
Biological Activity:
Measured by its ability to transfer sulfate from PAPS to heparan sulfate. The specific activity is > 20 pmoles/min/ug, as measured under the described conditions.
Endotoxin Level:
<1EU/ug (LAL method)
Storage and Stability:
May be stored at 4 degrees C for short-term only. Aliquot to avoid repeated freezing and thawing.. Store at -20 degrees C. Aliquots are stable for at least 6 months at -20 degrees C. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap. Further dilutions can be made in assay buffer.