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(2001). https://pubmed.ncbi.nlm.nih.gov/11175906/ DOI: 10.1038/84152","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Mitochondrial membrane-associated enzyme","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"a9a81e2a-b6a0-583d-be5c-ca277ea62cc0","evidence_kind":"source_excerpt","locator":"Lines 524-535","start_line":524,"end_line":535,"excerpt":"### iron-fech-clusters\nThe human ferrochelatase homodimer contained two uniquely coordinated, nitric-oxide-sensitive [2Fe-2S] clusters.\nCondition category: normal\nnutrient_topic: Iron research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: The enzyme that inserts iron also carries its own iron-sulfur cofactors.\norganism: Human enzyme\ntissue_or_cell_type: Mitochondrial membrane-associated enzyme\nexperimental_model: Human ferrochelatase crystal structure\nlimitations: Purified enzyme; cluster structure is not a human dietary-iron threshold.\nexposure: 2.0 angstrom structure and biochemical catalytic interpretation\nevidence_span: {\"source_cache\": \"artifacts/iron-research/11175906.abstract.txt\", \"locator\": \"Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"ba1c88d4630f6f0ee7f70989705c81162a2f8651c066f46b3aac73988b8dfa11\", \"start_char\": 0, \"end_char\": 770, \"text_sha256\": \"ba1c88d4630f6f0ee7f70989705c81162a2f8651c066f46b3aac73988b8dfa11\"}\n[iron-p11175906] The 2.0 A structure of human ferrochelatase, the terminal enzyme of heme biosynthesis. 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