{"id":"cdf91625-0b1d-5e80-84ea-b8e53eb31ca1","stable_key":"88eb7407-f147-558b-889b-0c89c4e0aa4a:spermidine-dhps-nad","predicate":"cofactor_for","statement":"Human DHPS binds NAD and spermidine; NAD-dependent chemistry initiates aminobutyl transfer.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"962d3981-b364-5ef9-ac98-f0f5326a3d87","mechanism_event_label":"A niacin-derived coenzyme participates in using spermidine.","subject":{"id":"283ed24b-06a1-50aa-9281-df3bac6ce37e","slug":"nad-plus","display_name":"NAD+","entity_type_key":"small_molecule"},"object":{"id":"33684e20-5166-55d6-9196-0793156787f1","slug":"dhps","display_name":"DHPS","entity_type_key":"protein"},"evidence_count":1,"mechanism_event":{"id":"962d3981-b364-5ef9-ac98-f0f5326a3d87","stable_key":"88eb7407-f147-558b-889b-0c89c4e0aa4a:spermidine-dhps-nad-event","event_type":"observed_relationship","label":"A niacin-derived coenzyme participates in using spermidine.","description":"Human DHPS binds NAD and spermidine; NAD-dependent chemistry initiates aminobutyl transfer.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"283ed24b-06a1-50aa-9281-df3bac6ce37e","slug":"nad-plus","display_name":"NAD+","entity_type_key":"small_molecule"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"33684e20-5166-55d6-9196-0793156787f1","slug":"dhps","display_name":"DHPS","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":"2f597a76-0e80-51ce-bed0-4859d7ae2685","slug":"eif5a1-k50","display_name":"eIF5A1 with unmodified Lys50","entity_type_key":"protein_state"},"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 full text","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Purified human DHPS crystallography and single-turnover assays.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"NAD is regenerated during the reaction; this does not measure NAD depletion or establish niacin supplementation benefit.","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":"A niacin-derived coenzyme participates in using spermidine.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"Half Way to Hypusine-Structural Basis for Substrate Recognition by Human Deoxyhypusine Synthase. · 2020 · https://pubmed.ncbi.nlm.nih.gov/32235505/ · DOI 10.3390/biom10040522","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"369e825d-bfa0-57ac-bebd-cb0d3d46c1c4","evidence_kind":"source_excerpt","locator":"Lines 14-20","start_line":14,"end_line":20,"excerpt":"## spermidine-dhps-nad\nA niacin-derived coenzyme participates in using spermidine.\nHuman DHPS binds NAD and spermidine; NAD-dependent chemistry initiates aminobutyl transfer.\nModel: Purified human DHPS crystallography and single-turnover assays.\nLimitations: NAD is regenerated during the reaction; this does not measure NAD depletion or establish niacin supplementation benefit.\nEvidence access: Primary full text\nHalf Way to Hypusine-Structural Basis for Substrate Recognition by Human Deoxyhypusine Synthase. · 2020 · https://pubmed.ncbi.nlm.nih.gov/32235505/ · DOI 10.3390/biom10040522","model_system":"Purified human DHPS crystallography and single-turnover assays.","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}