{"id":"6c6b0909-f0de-5103-95a6-c3aa70cd5b9a","stable_key":"e13b03e1-a614-543a-ac1b-97df18cfe30d:iron-chelation-rr","predicate":"depletion_reduced","statement":"Intracellular iron chelation removed the ribonucleotide-reductase tyrosyl radical, with depletion and regeneration kinetics depending on the chelator.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"1eb01714-6017-5a48-8595-7398889d2fe5","mechanism_event_label":"Iron locked away by a chelator was not equally available to maintain the DNA-synthesis enzyme.","subject":{"id":"d1a76588-8d56-5ba9-9fd1-16a82dc52b94","slug":"labile-cellular-iron","display_name":"Cellular labile iron pool","entity_type_key":"chemical_species"},"object":{"id":"cb1e9efc-6640-56c9-a8ec-1900d9b84ae6","slug":"rr-tyrosyl-radical","display_name":"Ribonucleotide reductase tyrosyl radical cofactor","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"1eb01714-6017-5a48-8595-7398889d2fe5","stable_key":"e13b03e1-a614-543a-ac1b-97df18cfe30d:iron-chelation-rr-event","event_type":"biochemical_relationship","label":"Iron locked away by a chelator was not equally available to maintain the DNA-synthesis enzyme.","description":"Intracellular iron chelation removed the ribonucleotide-reductase tyrosyl radical, with depletion and regeneration kinetics depending on the chelator.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"d1a76588-8d56-5ba9-9fd1-16a82dc52b94","slug":"labile-cellular-iron","display_name":"Cellular labile iron pool","entity_type_key":"chemical_species"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"cb1e9efc-6640-56c9-a8ec-1900d9b84ae6","slug":"rr-tyrosyl-radical","display_name":"Ribonucleotide reductase tyrosyl radical cofactor","entity_type_key":"cellular_process"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""}]},"contexts":[{"dimension":"evidence_span","value_text":"{\"source_cache\": \"artifacts/iron-research/8702762.abstract.txt\", \"locator\": \"Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"ceb70db961d5ae6f975c9edf1df28c495811a38189831240b8e3e61530b3a7f0\", \"start_char\": 0, \"end_char\": 1525, \"text_sha256\": \"ceb70db961d5ae6f975c9edf1df28c495811a38189831240b8e3e61530b3a7f0\"}","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Intracellular chelation with simultaneous EPR measurements","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"Hydroxypyridinone versus desferrioxamine chelation and washout","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Pharmacological cell experiment; radical loss is not a direct clinical measure of nutritional iron deficiency.","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 leukemia K562 cells","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"Iron locked away by a chelator was not equally available to maintain the DNA-synthesis enzyme.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[iron-p8702762] The relationship of intracellular iron chelation to the inhibition and regeneration of human ribonucleotide reductase. 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