Heparan sulfate 3-O-sulfotransferase1 (HS3ST1) transfers sulfate to the 3-OH position on glucosamine (GlcN) residues of heparan sulfate (HS) to form 3-O-sulfated HS. HS3ST1 is the rate limiting enzyme for synthesis of anticoagulant heparan sulfate. Unlike the other members of the HS3ST family, it is probably located in the Golgi lumen (Shworak et al. 1997).
[heparan sulfate]-glucosamine 3-sulfotransferase 1 activity of HS3ST1 [Golgi lumen]