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no D-plus-K supplementation regimen, K2-specific necessity, improved fracture outcome or obligatory supplement pairing was tested.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient","value_text":"Vitamin D2 and D3","comparator":null,"unit":null,"notes":"","entity":{"slug":"vitamin-d","display_name":"Vitamin D2 and D3","entity_type_key":"chemical_species"}},{"dimension":"nutrient_topic","value_text":"Vitamin D2 and D3 research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"vitamin-d","display_name":"Vitamin D2 and D3","entity_type_key":"chemical_species"}},{"dimension":"organism","value_text":"Bos taurus osteocalcin; liver-derived enzyme preparation","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"Osteocalcin needs a separate vitamin K-dependent protein-modification step; making more osteocalcin is not the same reaction.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[vdm-soute1987] Vitamin K-dependent carboxylase: increased efficiency of the carboxylation reaction. (1987). https://pubmed.ncbi.nlm.nih.gov/3495900/ DOI: 10.1055/s-0038-1651066","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Cell-free enzyme assay","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"a4894c43-e599-5d28-8fc0-80d8359c067e","evidence_kind":"source_excerpt","locator":"Lines 889-903","start_line":889,"end_line":903,"excerpt":"### vdm-vitamin-k-carboxylase-modifies-osteocalcin\nA concentrated vitamin K-dependent carboxylase preparation converted glutamate residues of decarboxylated bovine osteocalcin into gamma-carboxyglutamate in vitro.\nCondition category: normal\nnutrient_topic: Vitamin D2 and D3 research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Osteocalcin needs a separate vitamin K-dependent protein-modification step; making more osteocalcin is not the same reaction.\norganism: Bos taurus osteocalcin; liver-derived enzyme preparation\ntissue_or_cell_type: Cell-free enzyme assay\nexperimental_model: Microsomal vitamin K-dependent carboxylase enriched about 100-fold; bovine osteocalcin substrate and CO2-incorporation assay\nlimitations: In-vitro modification of a defined substrate; no D-plus-K supplementation regimen, K2-specific necessity, improved fracture outcome or obligatory supplement pairing was tested.\nexposure: 50 mM bicarbonate, excess enriched carboxylase and limiting decarboxylated osteocalcin; vitamin K-dependent reaction conditions.\ncross_nutrient: Vitamin D regulates osteocalcin expression in specified models; vitamin K-dependent carboxylation modifies its protein product through a distinct enzyme reaction.\nevidence_locator: Abstract: reported experimental results\nnutrient: Vitamin D2 and D3\nevidence_scope: D3 active metabolite or VDR machinery experiment; not a direct D2-versus-D3 comparison.\n[vdm-soute1987] Vitamin K-dependent carboxylase: increased efficiency of the carboxylation reaction. 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