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topical membership is not evidence of a direct dietary effect.\nplain_language: The activation chemistry can run backward experimentally.\norganism: Mus musculus\ntissue_or_cell_type: Recombinant enzyme\nexperimental_model: Purified recombinant mouse TPK1; forward and reverse reactions.\nlimitations: High AMP/Mg requirements do not establish meaningful reverse flux in humans.\ncross_nutrient: Mg dependence remains distinct from physiological net reaction direction.\nevidence_spans: [{\"source_document\": \"artifacts/thiamine_transport_sources/sambon-2022-tpk1-source-record.json\", \"source_field\": \"resultList.result[0].abstractText\", \"start_char\": 0, \"end_char\": 1689}]\nevidence_locator: Reaction definition and sections 2.2 and 3.3\nevidence-scope: Recombinant enzyme\n[sambon-2022-tpk1] Product inhibition of mammalian thiamine pyrophosphokinase is an important mechanism for maintaining thiamine diphosphate homeostasis (2022). https://doi.org/10.1016/j.bbagen.2021.130071 DOI: 10.1016/j.bbagen.2021.130071","model_system":"Purified recombinant mouse TPK1; 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Study references: [sambon-2022-tpk1] Product inhibition of mammalian thiamine pyrophosphokinase is an important mechanism for maintaining thiamine diphosphate homeostasis (2022). https://doi.org/10.1016/j.bbagen.2021.130071 DOI: 10.1016/j.bbagen.2021.130071","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}