{"id":"aabf50f4-6be2-59ae-acb0-9a85fa979678","stable_key":"0f17db03-207f-5910-ac8e-13dfc2f378ce:mg-tpk1-free-mg-restores-activity","predicate":"supports","statement":"Mg2+ in excess over ATP restored human TPK1 activity at low MgATP concentrations compared with a 1:1 total Mg:ATP ratio.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"positive","is_public":true,"mechanism_event_id":"ae28e987-8475-5a71-a852-6ae4e90ec703","mechanism_event_label":"The balance between ATP-bound and available magnesium affects activation of B1.","subject":{"id":"bff427ab-35f9-59c2-bb24-fd5953bbaec2","slug":"magnesium-ion","display_name":"Mg2+","entity_type_key":"ion"},"object":{"id":"2aa99fac-8e2a-50cb-9163-1c266796e1b6","slug":"tpk1","display_name":"Human thiamine pyrophosphokinase 1","entity_type_key":"protein"},"evidence_count":1,"mechanism_event":{"id":"ae28e987-8475-5a71-a852-6ae4e90ec703","stable_key":"0f17db03-207f-5910-ac8e-13dfc2f378ce:mg-tpk1-free-mg-restores-activity-event","event_type":"biochemical_relationship","label":"The balance between ATP-bound and available magnesium affects activation of B1.","description":"Mg2+ in excess over ATP restored human TPK1 activity at low MgATP concentrations compared with a 1:1 total Mg:ATP ratio.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"24904faf-f4b4-5e5a-a2e6-3549fb7a2a2e","slug":"mg-atp","display_name":"Magnesium-ATP complex","entity_type_key":"chemical_species"},"role":"substrate complex","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"58b974f1-d389-5bf6-81cd-889c44442c42","slug":"atp","display_name":"ATP","entity_type_key":"small_molecule"},"role":"Mg-binding substrate","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"36b7c3eb-068b-500f-af1c-078829df1ecc","slug":"thiamine","display_name":"Thiamine (vitamin B1)","entity_type_key":"small_molecule"},"role":"vitamin substrate","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"bff427ab-35f9-59c2-bb24-fd5953bbaec2","slug":"magnesium-ion","display_name":"Mg2+","entity_type_key":"ion"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""},{"entity":{"id":"2aa99fac-8e2a-50cb-9163-1c266796e1b6","slug":"tpk1","display_name":"Human thiamine pyrophosphokinase 1","entity_type_key":"protein"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":4,"notes":""}]},"contexts":[{"dimension":"cross_nutrient","value_text":"Magnesium availability supports vitamin B1 activation or cofactor use in the specified preparation; this does not establish a dietary threshold or universal treatment failure.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Purified His-tagged recombinant human TPK1, steady-state kinetics and mutations.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Total concentrations and speciation must be distinguished; no human Mg cutoff follows.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Magnesium research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"magnesium","display_name":"Magnesium","entity_type_key":"nutrient_element"}},{"dimension":"organism","value_text":"Homo sapiens","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"The balance between ATP-bound and available magnesium affects activation of B1.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[onozuka-2003-tpk1] Steady-state kinetics and mutational studies of recombinant human thiamin pyrophosphokinase (2003). https://pubmed.ncbi.nlm.nih.gov/12953792/ DOI: 10.3177/jnsv.49.156","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Purified recombinant enzyme","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"317a2e77-7ec5-503d-9b10-294144ace37b","evidence_kind":"source_excerpt","locator":"Lines 493-503","start_line":493,"end_line":503,"excerpt":"### mg-tpk1-free-mg-restores-activity\nMg2+ in excess over ATP restored human TPK1 activity at low MgATP concentrations compared with a 1:1 total Mg:ATP ratio.\nCondition category: normal\nnutrient_topic: Magnesium research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: The balance between ATP-bound and available magnesium affects activation of B1.\norganism: Homo sapiens\ntissue_or_cell_type: Purified recombinant enzyme\nexperimental_model: Purified His-tagged recombinant human TPK1, steady-state kinetics and mutations.\nlimitations: Total concentrations and speciation must be distinguished; no human Mg cutoff follows.\ncross_nutrient: Magnesium availability supports vitamin B1 activation or cofactor use in the specified preparation; this does not establish a dietary threshold or universal treatment failure.\n[onozuka-2003-tpk1] Steady-state kinetics and mutational studies of recombinant human thiamin pyrophosphokinase (2003). https://pubmed.ncbi.nlm.nih.gov/12953792/ DOI: 10.3177/jnsv.49.156","model_system":"Purified His-tagged recombinant human TPK1, steady-state kinetics and mutations.","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [onozuka-2003-tpk1] Steady-state kinetics and mutational studies of recombinant human thiamin pyrophosphokinase (2003). https://pubmed.ncbi.nlm.nih.gov/12953792/ DOI: 10.3177/jnsv.49.156","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"dd101e28-1a2e-5a48-9d1e-809c77514866","stable_key":"import-0f17db03-207f-5910-ac8e-13dfc2f378ce","title":"Magnesium: cross-nutrient mechanisms and deficiency (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":"e111c412f57143a17e8e65e74e8f7888b5bb9a61099873f4767f527fac19bb07","revision_id":"6b7f04f2-66ed-5859-955f-c2b50d4bf041","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}