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Fusion-protein assay does not quantify whole-body flux.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Vitamin C research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"vitamin-c","display_name":"Vitamin C","entity_type_key":"chemical_species"}},{"dimension":"organism","value_text":"Homo sapiens","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"The first carnitine-synthesis hydroxylation needs vitamin C support alongside iron and 2-oxoglutarate.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[tmlh2016] Substrate scope for trimethyllysine hydroxylase catalysis. 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