{"id":"14292f8c-22c2-5659-accc-989d0e54a7bc","stable_key":"46d15d9e-d3b5-544d-ba01-b785aa3e4f42:b1-coa-b5-downstream-biosynthesis","predicate":"is-enzymatically-converted-to","statement":"Purified human PPCS, PPCDC and bifunctional CoA synthase reconstituted CoA synthesis from phosphopantothenate in vitro.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"positive","is_public":true,"mechanism_event_id":"916cab18-00c5-54a4-b62b-a9edbe2e7ac9","mechanism_event_label":"Vitamin B5 supplies a separate carrier used after B1-dependent decarboxylation. 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The experiment starts with phosphorylated B5, so it does not test absorption or the first phosphorylation step.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[daugherty-2002-coa] Complete reconstitution of the human coenzyme A biosynthetic pathway via comparative genomics (2002). https://pubmed.ncbi.nlm.nih.gov/11923312/ DOI: 10.1074/jbc.m201708200","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Purified recombinant enzymes","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"97b648a2-1f1e-5727-a9cb-40855e985f44","evidence_kind":"source_excerpt","locator":"Lines 731-743","start_line":731,"end_line":743,"excerpt":"### b1-coa-b5-downstream-biosynthesis\nPurified human PPCS, PPCDC and bifunctional CoA synthase reconstituted CoA synthesis from phosphopantothenate in vitro.\nCondition category: normal\nnutrient_topic: Thiamine research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Vitamin B5 supplies a separate carrier used after B1-dependent decarboxylation. The experiment starts with phosphorylated B5, so it does not test absorption or the first phosphorylation step.\norganism: Homo sapiens\ntissue_or_cell_type: Purified recombinant enzymes\nexperimental_model: Reconstituted human enzyme pathway.\nlimitations: Cross-pathway connection is biochemical integration, not a tested clinical supplementation interaction.\nevidence: [{\"paper_key\": \"daugherty-2002-coa\", \"source_bundle\": \"artifacts/thiamine_metabolism_sources.json\", \"passage_ids\": [\"abstract\"], \"locator\": \"Primary publication abstract\", \"preservation\": \"Exact text retained in the source bundle; full source document retained when openly retrievable.\"}]\ncross_nutrient: Provides the B5-derived CoA partner required by PDH, OGDH, BCKDH and OADH; simultaneous B1/B5 depletion was not tested.\nnutrient: Thiamine (vitamin B1)\n[daugherty-2002-coa] Complete reconstitution of the human coenzyme A biosynthetic pathway via comparative genomics (2002). https://pubmed.ncbi.nlm.nih.gov/11923312/ DOI: 10.1074/jbc.m201708200","model_system":"Reconstituted human enzyme pathway.","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [daugherty-2002-coa] Complete reconstitution of the human coenzyme A biosynthetic pathway via comparative genomics (2002). https://pubmed.ncbi.nlm.nih.gov/11923312/ DOI: 10.1074/jbc.m201708200","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"158d2c03-ac8c-589f-8270-c468165ae346","stable_key":"import-46d15d9e-d3b5-544d-ba01-b785aa3e4f42","title":"Thiamine: mechanisms, deficiency and nutrient interactions (2026-09-17)","document_type":"imported_text","citation_label":"AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text.","file_path":"","sha256":"f376512fb3310141315548015b387833e3af45146e73fb73cd02cee20e4ddb9c","revision_id":"53bc5eda-dec8-58cc-a56f-a9eb4ab036ef","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}