A single protein catalyzes both N-deacetylation and N-sulfation during the biosynthesis of heparan sulfate.
Heparan sulfate is a highly sulfated carbohydrate polymer that binds to and modulates the activities of numerous proteins. The formation of these protein-binding domains in heparan sulfate is dependent on a series of biosynthetic reactions that modify the polysaccharide backbone; the initiating and rate-limiting steps of this process are the N-deacetylation and N-sulfation of N-acetylglucosamine residues in the polymer. We now report that in the rat liver, biosynthesis of heparan sulfate utilizes a single protein that possesses both N-deacetylase and N-sulfotransferase activities. This was accomplished by demonstrating that both activities resided in a purified soluble fusion protein containing the Golgi-lumenal portion of the enzyme. We propose that this protein be renamed the rat liver Golgi heparan sulfate N-deacetylase/N-sulfotransferase.
Wei
Z
Z
Glycomed Inc., Alameda, CA 94501.
Swiedler
S J
SJ
Ishihara
M
M
Orellana
A
A
Hirschberg
C B
CB
D000117:Acetylglucosamine / Q000378:metabolism*; D000581:Amidohydrolases / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D000818:Animals; D001483:Base Sequence; D002460:Cell Line; D002462:Cell Membrane / Q000201:enzymology; D003600:Cytosol / Q000201:enzymology; D004591:Electrophoresis, Polyacrylamide Gel; D006497:Heparan Sulfate / Q000096:biosynthesis*; D007700:Kinetics; D008099:Liver / Q000201:enzymology*; D008969:Molecular Sequence Data; D008970:Molecular Weight; D009838:Oligodeoxyribonucleotides; D051381:Rats; D011993:Recombinant Fusion Proteins / Q000302:isolation & purification / Q000378:metabolism; D015238:Sulfotransferases / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D014162:Transfection
D000117:Acetylglucosamine; D000581:Amidohydrolases; D006497:Heparan Sulfate; D009838:Oligodeoxyribonucleotides; D011993:Recombinant Fusion Proteins; D015238:Sulfotransferases; C021350:heparitin sulfotransferase