title: Structure Based Substrate Specificity Analysis of Heparan Sulfate 6-O-Sulfotransferases.
abstract: 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.
authors.affiliation: Division of Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina , Chapel Hill, North Carolina 27599, United States.
authors.forename: Yongmei
authors.initials: Y
authors.lastname: Xu
authors.affiliation: Genome Integrity and Structural Biology Laboratory, NIEHS, National Institutes of Health , Research Triangle Park, North Carolina 27709, United States.
authors.forename: Andrea F
authors.initials: AF
authors.lastname: Moon
authors.affiliation: Division of Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina , Chapel Hill, North Carolina 27599, United States.|School of Pharmaceutical Science, Jiangnan University , Wuxi 214122, China.
authors.forename: Shuqin
authors.initials: S
authors.lastname: Xu
authors.affiliation: Genome Integrity and Structural Biology Laboratory, NIEHS, National Institutes of Health , Research Triangle Park, North Carolina 27709, United States.
authors.forename: Juno M
authors.initials: JM
authors.lastname: Krahn
authors.affiliation: Division of Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina , Chapel Hill, North Carolina 27599, United States.
authors.forename: Jian
authors.identifier: 0000-0001-8552-1400
authors.initials: J
authors.lastname: Liu
authors.affiliation: Genome Integrity and Structural Biology Laboratory, NIEHS, National Institutes of Health , Research Triangle Park, North Carolina 27709, United States.
authors.forename: Lars C
authors.initials: LC
authors.lastname: Pedersen
mesh_terms: D000244:Adenosine Diphosphate / Q000737:chemistry / Q000378:metabolism*; D000595:Amino Acid Sequence; D000818:Animals; D020134:Catalytic Domain; D018360:Crystallography, X-Ray; D006801:Humans; D008958:Models, Molecular; D009844:Oligosaccharides / Q000737:chemistry / Q000378:metabolism*; D011487:Protein Conformation; D020033:Protein Isoforms / Q000737:chemistry / Q000378:metabolism; D016415:Sequence Alignment; D013379:Substrate Specificity; D015238:Sulfotransferases / Q000737:chemistry / Q000378:metabolism*; D015027:Zebrafish / Q000378:metabolism; D029961:Zebrafish Proteins / Q000737:chemistry / Q000378:metabolism
chemical_list: D009844:Oligosaccharides; D020033:Protein Isoforms; D029961:Zebrafish Proteins; D000244:Adenosine Diphosphate; C010840:adenosine 3'-phosphate-5'-phosphate; D015238:Sulfotransferases; C404189:heparan sulfate 6-O-sulfotransferase