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Sulfation is a separate step from P450 hydroxylation; no dietary sulfur threshold was established.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Melatonin research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"melatonin","display_name":"Melatonin","entity_type_key":"small_molecule"}},{"dimension":"organism","value_text":"Human recombinant enzymes, HepG2 and Caco-2 cells","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"The precursor has its own conjugation route, separate from melatonin methylation.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[melatonin-p26577053] Sulfation of 6-hydroxymelatonin, N-acetylserotonin and 4-hydroxyramelteon by the human cytosolic sulfotransferases (SULTs). (2016). https://pubmed.ncbi.nlm.nih.gov/26577053/ DOI: 10.3109/00498254.2015.1107656","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Sulfate conjugation","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"7d0e9a4a-8426-5ebb-8f9d-910fc932b121","evidence_kind":"source_excerpt","locator":"Lines 643-654","start_line":643,"end_line":654,"excerpt":"### melatonin-sult1c4\nSULT1C4 had the strongest tested sulfating activity toward N-acetylserotonin.\nCondition category: normal\nnutrient_topic: Melatonin research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: The precursor has its own conjugation route, separate from melatonin methylation.\norganism: Human recombinant enzymes, HepG2 and Caco-2 cells\ntissue_or_cell_type: Sulfate conjugation\nexperimental_model: Thirteen human SULT enzymes, labeled cells and tissue cytosols\nlimitations: Enzyme ranking applies to tested conditions. Sulfation is a separate step from P450 hydroxylation; no dietary sulfur threshold was established.\nexposure: 6-hydroxymelatonin and N-acetylserotonin substrates; sulfate metabolic labeling\nevidence_span: {\"source_cache\": \"artifacts/melatonin-research/26577053.abstract.txt\", \"locator\": \"Primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"ab887dc7012d5f393de52ecf842b67282d51b61bac705b9ab187c1a3e24331d5\", \"start_char\": 0, \"end_char\": 1378, \"text_sha256\": \"ab887dc7012d5f393de52ecf842b67282d51b61bac705b9ab187c1a3e24331d5\"}\n[melatonin-p26577053] Sulfation of 6-hydroxymelatonin, N-acetylserotonin and 4-hydroxyramelteon by the human cytosolic sulfotransferases (SULTs). 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