{"id":"7cdcd73a-b627-5acc-99d2-be187d24f69c","stable_key":"88eb7407-f147-558b-889b-0c89c4e0aa4a:spermidine-dohh-iron","predicate":"supports_diiron_center","statement":"Spectroscopy established a coupled diiron center in human DOHH, whose reduced state activates oxygen.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"ec70c103-ffd6-5104-88c1-64a533dbbfe1","mechanism_event_label":"Iron is part of the enzyme that completes hypusination.","subject":{"id":"59d6d1cd-df32-5b58-b950-3188bc7b95d6","slug":"iron-ii","display_name":"Ferrous iron","entity_type_key":"ion"},"object":{"id":"185dae5b-798b-5fd2-b28d-57b640045a0f","slug":"dohh","display_name":"DOHH","entity_type_key":"protein"},"evidence_count":1,"mechanism_event":{"id":"ec70c103-ffd6-5104-88c1-64a533dbbfe1","stable_key":"88eb7407-f147-558b-889b-0c89c4e0aa4a:spermidine-dohh-iron-event","event_type":"observed_relationship","label":"Iron is part of the enzyme that completes hypusination.","description":"Spectroscopy established a coupled diiron center in human DOHH, whose reduced state activates oxygen.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"59d6d1cd-df32-5b58-b950-3188bc7b95d6","slug":"iron-ii","display_name":"Ferrous iron","entity_type_key":"ion"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"185dae5b-798b-5fd2-b28d-57b640045a0f","slug":"dohh","display_name":"DOHH","entity_type_key":"protein"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"7014993c-468f-5c6b-ab04-80c87f9dfd9f","slug":"spermidine","display_name":"Spermidine","entity_type_key":"small_molecule"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"899c7ab0-6f81-5b38-a6bd-fbb33d66ac8d","slug":"oxygen","display_name":"Molecular oxygen","entity_type_key":"small_molecule"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""},{"entity":{"id":"a4d54591-b5a7-5e54-a52c-7011ace70819","slug":"eif5a1-deoxyhypusine","display_name":"eIF5A1 with deoxyhypusine at residue 50","entity_type_key":"protein_state"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":4,"notes":""}]},"contexts":[{"dimension":"evidence_access","value_text":"Primary abstract","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Purified recombinant human DOHH; EPR, Mossbauer, XAS and Raman spectroscopy.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Not a clinical iron-deficiency threshold or evidence that extra iron improves spermidine responses.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Spermidine collection; molecular form, preparation, species, exposure and manipulation remain explicit.","comparator":null,"unit":null,"notes":"","entity":{"slug":"spermidine","display_name":"Spermidine","entity_type_key":"small_molecule"}},{"dimension":"plain_language","value_text":"Iron is part of the enzyme that completes hypusination.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"Human deoxyhypusine hydroxylase, an enzyme involved in regulating cell growth, activates O2 with a nonheme diiron center. · 2009 · https://pubmed.ncbi.nlm.nih.gov/19706422/ · DOI 10.1073/pnas.0904553106","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"b90b90e6-7e6d-5b0e-8b83-fb8581902367","evidence_kind":"source_excerpt","locator":"Lines 54-60","start_line":54,"end_line":60,"excerpt":"## spermidine-dohh-iron\nIron is part of the enzyme that completes hypusination.\nSpectroscopy established a coupled diiron center in human DOHH, whose reduced state activates oxygen.\nModel: Purified recombinant human DOHH; EPR, Mossbauer, XAS and Raman spectroscopy.\nLimitations: Not a clinical iron-deficiency threshold or evidence that extra iron improves spermidine responses.\nEvidence access: Primary abstract\nHuman deoxyhypusine hydroxylase, an enzyme involved in regulating cell growth, activates O2 with a nonheme diiron center. · 2009 · https://pubmed.ncbi.nlm.nih.gov/19706422/ · DOI 10.1073/pnas.0904553106","model_system":"Purified recombinant human DOHH; EPR, Mossbauer, XAS and Raman spectroscopy.","directness":"reported_statement","verification_status":"source_derived_draft","notes":"Original curation paraphrase; evidence access and experimental limitations specified.","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"4348f3f8-0180-58a3-b61c-55d03bb322d2","stable_key":"import-88eb7407-f147-558b-889b-0c89c4e0aa4a","title":"Spermidine: biosynthesis, hypusination, transport and cross-nutrient mechanisms (2026-09-19)","document_type":"imported_text","citation_label":"AI-assisted research curation; primary references, access levels and experimental limitations individually identified. Not publisher full text.","file_path":"","sha256":"8eec8784bc2bd0384cfd53c6603c4ced8e53c227d9ab29ed85594c43e34c68ef","revision_id":"7c421a18-4526-59f6-b84e-4be533bc35ac","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}