{"id":"aaef3f8d-eb21-5d3e-b30d-15c91445dc6c","stable_key":"e13b03e1-a614-543a-ac1b-97df18cfe30d:iron-heme-oxygenase","predicate":"degrades","statement":"Heme oxygenase oxidatively cleaves heme to biliverdin with release of iron and carbon monoxide.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"ae532b06-6255-5125-a920-0d494fb9cb0a","mechanism_event_label":"Breaking open heme makes its iron available for reuse.","subject":{"id":"26298c7c-5265-5bf5-a435-e0fa98a3ac10","slug":"hmox1","display_name":"Human heme oxygenase 1 / HMOX1","entity_type_key":"protein"},"object":{"id":"2e1f7e0a-8b54-5ea3-9d34-01e7167f9097","slug":"heme","display_name":"Heme","entity_type_key":"small_molecule"},"evidence_count":1,"mechanism_event":{"id":"ae532b06-6255-5125-a920-0d494fb9cb0a","stable_key":"e13b03e1-a614-543a-ac1b-97df18cfe30d:iron-heme-oxygenase-event","event_type":"biochemical_relationship","label":"Breaking open heme makes its iron available for reuse.","description":"Heme oxygenase oxidatively cleaves heme to biliverdin with release of iron and carbon monoxide.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"4172f0c5-b7ea-5117-b62b-39be911d7531","slug":"biliverdin","display_name":"Biliverdin","entity_type_key":"small_molecule"},"role":"product","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"89bcaf42-b4ab-5760-8c2e-44eace10cee0","slug":"iron","display_name":"Iron","entity_type_key":"nutrient_element"},"role":"released_element","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"db0e1f0e-2a9c-51c6-9d2a-8d72e54fe901","slug":"carbon-monoxide","display_name":"Carbon monoxide","entity_type_key":"small_molecule"},"role":"product","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"26298c7c-5265-5bf5-a435-e0fa98a3ac10","slug":"hmox1","display_name":"Human heme oxygenase 1 / HMOX1","entity_type_key":"protein"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""},{"entity":{"id":"2e1f7e0a-8b54-5ea3-9d34-01e7167f9097","slug":"heme","display_name":"Heme","entity_type_key":"small_molecule"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":4,"notes":""}]},"contexts":[{"dimension":"evidence_span","value_text":"{\"source_cache\": \"artifacts/iron-research/15049686.abstract.txt\", \"locator\": \"Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"76bcb8ae12316350b1161f32c1633e2b5c752fcbf7e158940385b354ee3452d2\", \"start_char\": 0, \"end_char\": 1167, \"text_sha256\": \"76bcb8ae12316350b1161f32c1633e2b5c752fcbf7e158940385b354ee3452d2\"}","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Product-bound human HO-1 structure","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"Biliverdin-bound structure compared with heme-bound enzyme","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Product release interpretation from structure; no in-vivo flux measurement.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Iron research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"iron","display_name":"Iron","entity_type_key":"nutrient_element"}},{"dimension":"organism","value_text":"Human enzyme","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"Breaking open heme makes its iron available for reuse.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[iron-p15049686] Crystal structure of human heme oxygenase-1 in a complex with biliverdin. 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