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(1984). https://pubmed.ncbi.nlm.nih.gov/6325436/ DOI: 10.1016/s0021-9258(18)91023-9","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Chick embryo enzyme preparations","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"c97b1d0b-35e5-52a8-b324-6286442ee4ea","evidence_kind":"source_excerpt","locator":"Lines 585-596","start_line":585,"end_line":596,"excerpt":"### vc-enzyme-coupled-ascorbate-use\nIn chick collagen hydroxylase assays, complete proline hydroxylation was coupled to 2-oxoglutarate decarboxylation while ascorbate was not consumed in most catalytic cycles.\nCondition category: normal\nnutrient_topic: Vitamin C research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Vitamin C is not a one-for-one consumed ingredient in every successful collagen hydroxylation.\norganism: Gallus gallus\ntissue_or_cell_type: Chick embryo enzyme preparations\nexperimental_model: Purified chick prolyl and partially purified lysyl collagen hydroxylases\nlimitations: This statement concerns coupled turnover; it must not be transferred to copper monooxygenases.\ncross_nutrient: Vitamin C chemistry in collagen, modified-lysine/carnitine metabolism or copper-dependent peptide/catecholamine processing.\nexposure: Peptide substrate present or absent; uncoupled 2-oxoglutarate decarboxylation assays.\n[myllyla1984] Ascorbate is consumed stoichiometrically in the uncoupled reactions catalyzed by prolyl 4-hydroxylase and lysyl hydroxylase. 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