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It is a rat enzyme structure with a cofactor analogue, not a measurement of iron status in an animal.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Cold water immersion research collection; topical membership is not evidence of a direct clinical effect, and a therapeutic exposure is not a dietary intake.","comparator":null,"unit":null,"notes":"","entity":{"slug":"cold-water-immersion","display_name":"Cold water immersion","entity_type_key":"drug"}},{"dimension":"organism","value_text":"Rat enzyme","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"The first and slowest step of making noradrenaline needs an iron atom and a molecule of oxygen.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[cold-p9753429] Crystal structure of tyrosine hydroxylase with bound cofactor analogue and iron at 2.3 A resolution: self-hydroxylation of Phe300 and the pterin-binding site. 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It is a rat enzyme structure with a cofactor analogue, not a measurement of iron status in an animal.\nexposure: Bound 7,8-dihydrobiopterin and iron\nevidence_span: {\"source_cache\": \"artifacts/cold-research/9753429.abstract.txt\", \"locator\": \"Indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"3c76ec6d5dadb463c0a044175d5a78fbd02df4da7c339029c8c232e8878175b9\", \"start_char\": 0, \"end_char\": 1695, \"text_sha256\": \"3c76ec6d5dadb463c0a044175d5a78fbd02df4da7c339029c8c232e8878175b9\"}\n[cold-p9753429] Crystal structure of tyrosine hydroxylase with bound cofactor analogue and iron at 2.3 A resolution: self-hydroxylation of Phe300 and the pterin-binding site. 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