Characterization of the N-deacetylase domain from the heparan sulfate N-deacetylase/N-sulfotransferase 2

Biochem Biophys Res Commun. 2006 Jan 27;339(4):1232-7. doi: 10.1016/j.bbrc.2005.11.142. Epub 2005 Dec 6.

Abstract

Heparin and heparan sulfate are linear sulfated polysaccharides that exert a multitude of biological functions. Heparan sulfate glucosaminyl N-deacetylase/N-sulfotransferase isoform 2 (NDST-2), a key enzyme in the biosynthesis of heparin, contains two distinct activities. This bifunctional enzyme removes the acetyl group from N-acetylated glucosamine (N-deacetylase activity) and transfers a sulfuryl group to the unsubstituted amino position (N-sulfotransferase activity). The N-sulfotransferase activity of NDST has been unambiguously localized to the C-terminal domain of NDST. Here, we report that the N-terminal domain of NDST-2 retains N-deacetylase activity. The N-terminal domain (A66-P604) of human NDST-2, designated as N-deacetylase (NDase), was cloned as a (His)(6)-fusion protein, and protein expression was carried out in Escherichia coli. Heparosan treated with NDase contains N-unsubstituted glucosamine and is highly susceptible to N-sulfation by N-sulfotransferase. Our results conclude that the N-terminal domain of NDST-2 contains functional N-deacetylase activity. This finding helps further elucidate the mechanism of action of heparan sulfate N-deacetylase/N-sulfotransferases and the biosynthesis of heparan sulfate in general.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Binding Sites
  • Enzyme Activation
  • Escherichia coli / enzymology*
  • Heparitin Sulfate / chemistry*
  • Heparitin Sulfate / metabolism*
  • Protein Binding
  • Protein Structure, Tertiary
  • Structure-Activity Relationship
  • Sulfotransferases / chemistry*
  • Sulfotransferases / metabolism*

Substances

  • Heparitin Sulfate
  • Sulfotransferases
  • heparitin sulfotransferase