{"doi":"10.17615/d9xr-e616","title":"Molecular Mechanism of Substrate Specificity for Heparan Sulfate 2- O -Sulfotransferase","abstract":"Heparan sulfate (HS) is an abundant polysaccharide in the animal kingdom with essential physiological functions. HS is composed of sulfated saccharides that are biosynthesized through a complex pathway involving multiple enzymes. In vivo regulation of this process remains unclear. HS 2-O-sulfotransferase (2OST) is a key enzyme in this pathway. Here, we report the crystal structure of the ternary complex of 2OST, 3′-phosphoadenosine 5′-phosphate, and a heptasaccharide substrate. Utilizing site-directed mutagenesis and specific oligosaccharide substrate sequences, we probed the molecular basis of specificity and 2OST position in the ordered HS biosynthesis pathway. These studies revealed that Arg-80, Lys-350, and Arg-190 of 2OST interact with the N-sulfo groups near the modification site, consistent with the dependence of 2OST on N-sulfation. In contrast, 6-O-sulfo groups on HS are likely excluded by steric and electrostatic repulsion within the active site supporting the hypothesis that 2-O-sulfation occurs prior to 6-O-sulfation. Our results provide the structural evidence for understanding the sequence of enzymatic events in this pathway.","journal":"UNC Libraries","year":2020,"id":117684,"datarank":0.0,"base_score":0.0,"endowment":0.0,"self_citation_contribution":0.0,"citation_network_contribution":0.0,"self_endowment_contribution":0.0,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":1,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9595,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2020-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":342596,"name":"Lars C. Pedersen","orcid":"0000-0002-4488-4077","position":1,"is_corresponding":false},{"id":73934,"name":"Wenfang Dou","orcid":null,"position":2,"is_corresponding":false},{"id":548351,"name":"Juzheng Sheng","orcid":"0000-0003-2856-9162","position":3,"is_corresponding":false},{"id":548988,"name":"Po-Hung Hsieh","orcid":null,"position":4,"is_corresponding":false},{"id":548352,"name":"Chunhui Liu","orcid":"0000-0001-5886-5208","position":5,"is_corresponding":false},{"id":47681,"name":"L. Perera","orcid":"0000-0003-0823-1631","position":6,"is_corresponding":false},{"id":288975,"name":"Yongmei Xu","orcid":"0000-0002-3756-581X","position":7,"is_corresponding":false},{"id":288986,"name":"Jian Liu","orcid":"0000-0001-8552-1400","position":8,"is_corresponding":false},{"id":398021,"name":"J.M. Krahn","orcid":"0000-0002-4640-0267","position":0,"is_corresponding":true}],"reference_count":0,"raw_metadata":null,"created_at":"2026-07-18T23:13:54.951170Z","pmid":null,"pmcid":null,"fwci":null,"citation_percentile":null,"influential_citations":0,"oa_status":null,"license":null,"views":0,"total_file_size_bytes":0,"version_count":0,"fair_f":null,"fair_a":null,"fair_i":null,"fair_r":null,"fair_zscore":null,"fair_rationale":null,"fair_model":null,"fair_agent_version":null,"fair_fulltext_source":null,"fair_has_llm":null,"fair_computed_at":null,"clinical_trials":[],"software_tools":[],"db_accessions":[],"linked_datasets":[],"topics":[]}