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(2006). https://pubmed.ncbi.nlm.nih.gov/16765986/ DOI: 10.1016/j.jmb.2006.05.036","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Purified oxy-, deoxy- and carbonmonoxyhemoglobin","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"4bac2825-68c8-5c08-940b-fb6f358238c8","evidence_kind":"source_excerpt","locator":"Lines 537-548","start_line":537,"end_line":548,"excerpt":"### iron-hemoglobin-oxygen-site\nOxyhemoglobin structures resolved hydrogen bonding between the oxygen ligand and distal histidine in both alpha and beta subunits.\nCondition category: normal\nnutrient_topic: Iron research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Hemoglobin holds oxygen at carefully organized heme sites so oxygen binding can be controlled.\norganism: Human hemoglobin A\ntissue_or_cell_type: Purified oxy-, deoxy- and carbonmonoxyhemoglobin\nexperimental_model: High-resolution crystallographic comparison\nlimitations: Structural oxygen-ligand geometry, not a supplementation or oxygen-delivery clinical trial.\nexposure: 1.25 angstrom structural refinement\nevidence_span: {\"source_cache\": \"artifacts/iron-research/16765986.abstract.txt\", \"locator\": \"Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"177ab81c08f82c99c81c69d1cb582e52216234e290066ae5aa380a887fb0e38c\", \"start_char\": 0, \"end_char\": 1284, \"text_sha256\": \"177ab81c08f82c99c81c69d1cb582e52216234e290066ae5aa380a887fb0e38c\"}\n[iron-p16765986] 1.25 A resolution crystal structures of human haemoglobin in the oxy, deoxy and carbonmonoxy forms. 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