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(2010). https://pubmed.ncbi.nlm.nih.gov/19819904/ DOI: 10.1093/jb/mvp152","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Purified recombinant protein; no intact tissue","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"d9578b81-2215-5525-8410-a3ea426c68ec","evidence_kind":"source_excerpt","locator":"Lines 369-380","start_line":369,"end_line":380,"excerpt":"### b3-pre-nampt-reaction\nHuman NAMPT converts nicotinamide and PRPP to nicotinamide mononucleotide and pyrophosphate.\nCondition category: normal\nnutrient_topic: Niacin research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Nicotinamide salvage first makes NMN.\norganism: Homo sapiens\ntissue_or_cell_type: Purified recombinant protein; no intact tissue\nexperimental_model: Purified human NAMPT reaction monitoring by 1H/31P NMR and substrate/product crystallography\nlimitations: Purified-enzyme evidence does not establish dietary intake requirements or clinical outcomes.\nexposure: Biochemical or structural assay; no dietary intervention\nevidence_span: {\"source_cache\": \"artifacts/niacin-precursors-sources/nampt2009.abstract.txt\", \"locator\": \"Indexed primary abstract\", \"start_char\": 0, \"end_char\": 1272, \"file_sha256\": \"b67ca4decafccfc4132deba87ffddf2114e60542c77fa4354165d414aa0f13c5\", \"text_sha256\": \"b67ca4decafccfc4132deba87ffddf2114e60542c77fa4354165d414aa0f13c5\"}\n[b3-pre-nampt2009] Structure and reaction mechanism of human nicotinamide phosphoribosyltransferase. 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