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NADP+ production is distinct from its later reduction to NADPH.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"evidence_span","value_text":"{\"source_cache\": \"artifacts/niacin-redox-sources/nadk-human-2025.fulltext.txt\", \"locator\": \"Results\", \"start_char\": 53525, \"end_char\": 54577, \"file_sha256\": \"72c7b9625e1bf4137d6833adac6ae49fc108f2cd75bb4945c5b04d72a0355f9b\", \"text_sha256\": \"db49fc47ad605562e1c1cf93e1b39596505906831ae509e7ec0031485f84ba4f\"}","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Full-length recombinant human NADK; G6PD-coupled assay","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"5 mM MgATP; 0.1–2 mM NAD+; 1 mM additional MgCl2; 30°C","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Scoped experimental observation; no dietary niacin or magnesium deficiency threshold or treatment benefit was tested.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Niacin research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"niacin","display_name":"Niacin (vitamin B3)","entity_type_key":"nutrient_element"}},{"dimension":"organism","value_text":"Homo sapiens","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"The cytosolic kinase makes the phosphorylated cofactor using magnesium-associated ATP.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[nadk-human-2025] Cryo-EM structure and regulation of human NAD kinase. 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NADP+ production is distinct from its later reduction to NADPH.\nevidence_span: {\"source_cache\": \"artifacts/niacin-redox-sources/nadk-human-2025.fulltext.txt\", \"locator\": \"Results\", \"start_char\": 53525, \"end_char\": 54577, \"file_sha256\": \"72c7b9625e1bf4137d6833adac6ae49fc108f2cd75bb4945c5b04d72a0355f9b\", \"text_sha256\": \"db49fc47ad605562e1c1cf93e1b39596505906831ae509e7ec0031485f84ba4f\"}\n[nadk-human-2025] Cryo-EM structure and regulation of human NAD kinase. (2025). https://pubmed.ncbi.nlm.nih.gov/39854463/ DOI: 10.1126/sciadv.ads2664","model_system":"Full-length recombinant human NADK; G6PD-coupled assay","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [nadk-human-2025] Cryo-EM structure and regulation of human NAD kinase. 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