Publications

• The occurrence of three isoforms of heparan sulfate 6-O-sulfotransferase having different specificities for hexuronic acid adjacent to the targeted N-sulfoglucosamine.

  Habuchi H., Tanaka M., Habuchi O., Yoshida K., Suzuki H., Ban K., Kimata K.

  We previously cloned heparan sulfate 6-O-sulfotransferase (HS6ST) (Habuchi, H., Kobayashi, M., and Kimata, K. (1998) J. Biol. Chem. 273, 9208-9213). In this study, we report the cloning and characterization of three mouse isoforms of HS6ST, a mouse homologue to the original human HS6ST (HS6ST-1) a ... >> More

  We previously cloned heparan sulfate 6-O-sulfotransferase (HS6ST) (Habuchi, H., Kobayashi, M., and Kimata, K. (1998) J. Biol. Chem. 273, 9208-9213). In this study, we report the cloning and characterization of three mouse isoforms of HS6ST, a mouse homologue to the original human HS6ST (HS6ST-1) and two novel HS6STs (HS6ST-2 and HS6ST-3). The cDNAs have been obtained from mouse brain cDNA library by cross-hybridization with human HS6ST cDNA. The three cDNAs contained single open reading frames that predicted type II transmembrane proteins composed of 401, 506, and 470 amino acid residues, respectively. Amino acid sequence of HS6ST-1 was 51 and 57% identical to those of HS6ST-2 and HS6ST-3, respectively. HS6ST-2 and HS6ST-3 had the 50% identity. Overexpression of each isoform in COS-7 cells resulted in about 10-fold increase of HS6ST activity. The three isoforms purified with anti-FLAG antibody affinity column transferred sulfate to heparan sulfate and heparin but not to other glycosaminoglycans. Each isoform showed different specificity toward the isomeric hexuronic acid adjacent to the targeted N-sulfoglucosamine; HS6ST-1 appeared to prefer the iduronosyl N-sulfoglucosamine while HS6ST-2 had a different preference, depending upon the substrate concentrations, and HS6ST-3 acted on either substrate. Northern analysis showed that the expression of each message in various tissues was characteristic to the respective isoform. HS6ST-1 was expressed strongly in liver, and HS6ST-2 was expressed mainly in brain and spleen. In contrast, HS6ST-3 was expressed rather ubiquitously. These results suggest that the expression of these isoforms may be regulated in tissue-specific manners and that each isoform may be involved in the synthesis of heparan sulfates with tissue-specific structures and functions. << Less

  J. Biol. Chem. 275:2859-2868(2000) [PubMed] [EuropePMC]

• Structure based substrate specificity analysis of heparan sulfate 6-O-sulfotransferases.

  Xu Y., Moon A.F., Xu S., Krahn J.M., Liu J., Pedersen L.C.

  Heparan sulfate (HS) is a sulfated polysaccharide exhibiting essential physiological functions. HS 6-O-sulfotransferase (6-OST) transfers a sulfo group to the 6-OH position of glucosamine units to confer a variety of HS biological activities. There are three different isoforms of 6-OST in the huma ... >> More

  Heparan sulfate (HS) is a sulfated polysaccharide exhibiting essential physiological functions. HS 6-O-sulfotransferase (6-OST) transfers a sulfo group to the 6-OH position of glucosamine units to confer a variety of HS biological activities. There are three different isoforms of 6-OST in the human genome. Here, we report crystal structures of the ternary complex of 6-OST with the sulfo donor analog 3'-phosphoadenosine 5'-phosphate and three different oligosaccharide substrates at 1.95 to 2.1 Å resolutions. Structural and mutational analyses reveal amino acid residues that contribute to catalysis and substrate recognition of 6-OST. Unexpectedly, the structures reveal 6-OST engages HS in a completely different orientation than other HS sulfotransferases and sheds light on the basic HS requirements for specificity. These findings also contribute structural information to understand mutations in human 6-OST isoform 1 associated with the human genetic disease idiopathic hypogonadotropic hypogonadism characterized by incomplete or lack of puberty. << Less

  ACS Chem. Biol. 12:73-82(2017) [PubMed] [EuropePMC]

• Purification and characterization of heparan sulfate 6-sulfotransferase from the culture medium of Chinese hamster ovary cells.

  Habuchi H., Habuchi O., Kimata K.

  Heparan sulfate 6-sulfotransferase, which catalyzes the transfer of sulfate from 3'-phosphoadenylyl sulfate to position 6 of N-sulfoglucosamine in heparan sulfate, was purified 10,700-fold to apparent homogeneity with a 40% yield from the serum-free culture medium of Chinese hamster ovary cells. T ... >> More

  Heparan sulfate 6-sulfotransferase, which catalyzes the transfer of sulfate from 3'-phosphoadenylyl sulfate to position 6 of N-sulfoglucosamine in heparan sulfate, was purified 10,700-fold to apparent homogeneity with a 40% yield from the serum-free culture medium of Chinese hamster ovary cells. The isolation procedure included affinity chromatography of the first heparin-Sepharose CL-6B column (stepwise elution), 3',5'-ADP-agarose, and the second heparin-Sepharose CL-6B column (gradient elution). Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the purified enzyme showed two protein bands with molecular masses of 52 and 45 kDa. Both proteins appeared to be glycoproteins, because their molecular masses decreased after N-glycanase digestion. When completely desulfated and N-resulfated heparin was used as acceptor, the purified enzyme transferred sulfate to position 6 of N-sulfoglucosamine residue but did not transfer sulfate to the amino group of glucosamine residue or to position 2 of the iduronic acid residue. Heparan sulfate was also sulfated by the purified enzyme at position 6 of N-sulfoglucosamine residue. Chondroitin and chondroitin sulfate did not serve as acceptors. The optimal pH for enzyme activity was around 6.3. The enzyme activity was inhibited by dithiothreitol and was stimulated strongly by protamine. The Km value for adenosine 3'-phosphate 5'-phosphosulfate was 0.44 microM. << Less

  J. Biol. Chem. 270:4172-4179(1995) [PubMed] [EuropePMC]