{"doi":"10.1093/mtomcs/mfab056","title":"Active site characterization and activity of the human aspartyl (asparaginyl) β-hydroxylase","abstract":"<jats:title>Abstract</jats:title>\n               <jats:p>Human aspartyl/asparaginyl beta-hydroxylase (HAAH) is a member of the superfamily of nonheme Fe2+/α-ketoglutarate (αKG) dependent oxygenase enzymes with a noncanonical active site. HAAH hydroxylates epidermal growth factor (EGF) like domains to form the β-hydroxylated product from substrate asparagine or aspartic acid and has been suggested to have a negative impact in a variety of cancers. In addition to iron, HAAH also binds divalent calcium, although the role of the latter is not understood. Herein, the metal binding chemistry and influence on enzyme stability and activity have been evaluated by a combined biochemical and biophysical approach. Metal binding parameters for the HAAH active site were determined by use of isothermal titration calorimetry, demonstrating a high-affinity regulatory binding site for Ca2+ in the catalytic domain in addition to the catalytic Fe2+ cofactor. We have analyzed various active site derivatives, utilizing LC-MS and a new HPLC technique to determine the role of metal binding and the second coordination sphere in enzyme activity, discovering a previously unreported residue as vital for HAAH turnover. This analysis of the in vitro biochemical function of HAAH furthers the understanding of its importance to cellular biochemistry and metabolic pathways.</jats:p>","journal":"Metallomics","year":2021,"id":630869,"datarank":0.3596842909197557,"base_score":2.3978952727983707,"endowment":2.3978952727983707,"self_citation_contribution":0.3596842909197557,"citation_network_contribution":0.0,"self_endowment_contribution":0.3596842909197557,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":10,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":null,"is_data_producer":false,"deposit_databanks":null,"is_oa":false,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":null,"fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":1634610,"name":"Andrew M Pinkham","orcid":null,"position":1,"is_corresponding":false},{"id":799864,"name":"Zechariah Thompson","orcid":"0000-0001-9377-9540","position":2,"is_corresponding":false},{"id":1634611,"name":"J A Cowan","orcid":null,"position":3,"is_corresponding":false},{"id":1634609,"name":"Jenna M Greve","orcid":null,"position":0,"is_corresponding":false}],"reference_count":0,"raw_metadata":{"has_enrichment":true,"resolved":true,"title":"Active site characterization and activity of the human aspartyl (asparaginyl) β-hydroxylase","abstract":"<jats:title>Abstract</jats:title>\n               <jats:p>Human aspartyl/asparaginyl beta-hydroxylase (HAAH) is a member of the superfamily of nonheme Fe2+/α-ketoglutarate (αKG) dependent oxygenase enzymes with a noncanonical active site. HAAH hydroxylates epidermal growth factor (EGF) like domains to form the β-hydroxylated product from substrate asparagine or aspartic acid and has been suggested to have a negative impact in a variety of cancers. In addition to iron, HAAH also binds divalent calcium, although the role of the latter is not understood. Herein, the metal binding chemistry and influence on enzyme stability and activity have been evaluated by a combined biochemical and biophysical approach. Metal binding parameters for the HAAH active site were determined by use of isothermal titration calorimetry, demonstrating a high-affinity regulatory binding site for Ca2+ in the catalytic domain in addition to the catalytic Fe2+ cofactor. We have analyzed various active site derivatives, utilizing LC-MS and a new HPLC technique to determine the role of metal binding and the second coordination sphere in enzyme activity, discovering a previously unreported residue as vital for HAAH turnover. This analysis of the in vitro biochemical function of HAAH furthers the understanding of its importance to cellular biochemistry and metabolic pathways.</jats:p>","is_dataset_classified":null,"base_score":2.302585092994046,"endowment":2.302585092994046,"datacite_reuse_total":0,"file_count":0,"downloads":0,"views":0,"has_version_chain":false,"is_dataset":false,"is_oa":false,"pmid":"34543426","pmcid":null,"openalex_id":"https://openalex.org/W3199132062","authors":[],"funders":[{"funder_name":"National Science Foundation","grant_id":"CHE-1800239","title":null},{"funder_name":"National Science Foundation","grant_id":"1800239","title":"Artificial Glycosidases"}],"total_grants":2,"fwci":0.8371,"citation_percentile":0.6958099,"influential_citations":0,"citation_trend":[{"year":2022,"count":2},{"year":2024,"count":4},{"year":2025,"count":2},{"year":2026,"count":1}],"oa_status":"hybrid","license":"cc-by","oa_locations":[{"url":"https://doi.org/10.1093/mtomcs/mfab056","host_type":"journal"},{"url":"https://doi.org/10.1093/mtomcs/mfab056","host_type":"publisher"},{"url":"http://academic.oup.com/metallomics/advance-article-pdf/doi/10.1093/mtomcs/mfab056/40417590/mfab056.pdf","host_type":"publisher"},{"url":"https://academic.oup.com/metallomics/article-pdf/13/10/mfab056/41653554/mfab056.pdf","host_type":"publisher"},{"url":"https://pubmed.ncbi.nlm.nih.gov/34543426","host_type":"repository"},{"url":"https://dx.doi.org/10.1093/mtomcs/mfab056","host_type":""}],"fields_of_study":["Metabolism and Genetic Disorders","Aldose Reductase and Taurine","Biochemical and Molecular Research","0301 basic medicine","0303 health sciences","03 medical and health sciences"],"mesh_terms":["Calcium","Calorimetry","Chromatography, High Pressure Liquid","Ferrous Compounds","Humans","Mixed Function Oxygenases","Isoenzymes","Kinetics","Models, Molecular","Phenylhydrazines","Catalytic Domain","Tandem Mass Spectrometry"],"keywords":["Chemistry","Characterization (materials science)","Biochemistry","Stereochemistry","Materials science","Nanotechnology","Calcium","EGF","Itc","Alpha-ketoglutarate","Nonheme Iron","Haah","Models, Molecular","Calorimetry","Mixed Function Oxygenases","Phenylhydrazines","Isoenzymes","Kinetics","Tandem Mass Spectrometry","Catalytic Domain","Humans","Ferrous Compounds","Chromatography, High Pressure Liquid"],"sdg_mappings":[{"sdg_number":3,"sdg_label":"3. 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