{"id":"e9f02c1b-6a01-59bf-a123-0f4c4b1c06a7","stable_key":"46d15d9e-d3b5-544d-ba01-b785aa3e4f42:b1-tkt-nonoxidative-carbon-transfer","predicate":"transfers-two-carbon-unit-in","statement":"Human TKT transfers two carbons from xylulose-5-phosphate to ribose-5-phosphate, yielding glyceraldehyde-3-phosphate and sedoheptulose-7-phosphate.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"positive","is_public":true,"mechanism_event_id":"325b8449-f2ca-5b05-8165-7dbf8ea1a996","mechanism_event_label":"B1 supports sugar rearrangement, connecting pentose and glycolytic intermediates. 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This reaction does not directly make NADPH.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[mitschke-2010-tkt] The crystal structure of human transketolase and new insights into its mode of action (2010). https://pubmed.ncbi.nlm.nih.gov/20667822/ DOI: 10.1074/jbc.m110.149955","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Purified enzyme","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"3e8f5ad3-1164-53ba-96d3-e783df747086","evidence_kind":"source_excerpt","locator":"Lines 950-961","start_line":950,"end_line":961,"excerpt":"### b1-tkt-nonoxidative-carbon-transfer\nHuman TKT transfers two carbons from xylulose-5-phosphate to ribose-5-phosphate, yielding glyceraldehyde-3-phosphate and sedoheptulose-7-phosphate.\nCondition category: normal\nnutrient_topic: Thiamine research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: B1 supports sugar rearrangement, connecting pentose and glycolytic intermediates. This reaction does not directly make NADPH.\norganism: Homo sapiens\ntissue_or_cell_type: Purified enzyme\nexperimental_model: Recombinant human TKT reaction analysis.\nlimitations: Direct reaction chemistry; indirect recycling effects on oxidative PPP flux need separate evidence.\nevidence: [{\"paper_key\": \"mitschke-2010-tkt\", \"source_bundle\": \"artifacts/thiamine_metabolism_sources.json\", \"passage_ids\": [\"p-12\"], \"locator\": \"simplified reaction scheme\", \"preservation\": \"Exact text retained in the source bundle; full source document retained when openly retrievable.\"}]\nnutrient: Thiamine (vitamin B1)\n[mitschke-2010-tkt] The crystal structure of human transketolase and new insights into its mode of action (2010). https://pubmed.ncbi.nlm.nih.gov/20667822/ DOI: 10.1074/jbc.m110.149955","model_system":"Recombinant human TKT reaction analysis.","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [mitschke-2010-tkt] The crystal structure of human transketolase and new insights into its mode of action (2010). https://pubmed.ncbi.nlm.nih.gov/20667822/ DOI: 10.1074/jbc.m110.149955","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}