{"id":"0b1c586e-70e8-5a35-9b45-c3a7962f92e8","stable_key":"0f17db03-207f-5910-ac8e-13dfc2f378ce:mg-nka-isotope-atp-sodium-coupling","predicate":"powers","statement":"In Mg-loaded human red-cell ghosts, ouabain-sensitive hydrolysis of one ATP accompanied loss of about three sodium ions.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"positive","is_public":true,"mechanism_event_id":"d16ba3c1-263f-5d56-90fc-fee60e36ccab","mechanism_event_label":"ATP turnover was directly linked to outward sodium pumping in a magnesium-containing preparation.","subject":{"id":"58b974f1-d389-5bf6-81cd-889c44442c42","slug":"atp","display_name":"ATP","entity_type_key":"small_molecule"},"object":{"id":"77f557fd-965b-58d8-a2b4-6c0102f5ea41","slug":"sodium-pump-sodium-efflux","display_name":"Sodium-pump-mediated sodium efflux","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"d16ba3c1-263f-5d56-90fc-fee60e36ccab","stable_key":"0f17db03-207f-5910-ac8e-13dfc2f378ce:mg-nka-isotope-atp-sodium-coupling-event","event_type":"biochemical_relationship","label":"ATP turnover was directly linked to outward sodium pumping in a magnesium-containing preparation.","description":"In Mg-loaded human red-cell ghosts, ouabain-sensitive hydrolysis of one ATP accompanied loss of about three sodium ions.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"bff427ab-35f9-59c2-bb24-fd5953bbaec2","slug":"magnesium-ion","display_name":"Mg2+","entity_type_key":"ion"},"role":"loaded cofactor","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"38de8704-84db-5770-ac1d-242cd787e798","slug":"sodium-ion","display_name":"Sodium ion","entity_type_key":"ion"},"role":"transported ion","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"27c3e7bd-c6e1-5344-8130-b231a9da2cfb","slug":"sodium-potassium-atpase","display_name":"Sodium-potassium ATPase complexes","entity_type_key":"protein_family"},"role":"pump","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"5dd31e52-f51e-51f3-880e-240abcc0ab1d","slug":"potassium-ion","display_name":"Potassium ion","entity_type_key":"ion"},"role":"external activator","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""},{"entity":{"id":"58b974f1-d389-5bf6-81cd-889c44442c42","slug":"atp","display_name":"ATP","entity_type_key":"small_molecule"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":4,"notes":""},{"entity":{"id":"77f557fd-965b-58d8-a2b4-6c0102f5ea41","slug":"sodium-pump-sodium-efflux","display_name":"Sodium-pump-mediated sodium efflux","entity_type_key":"cellular_process"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":5,"notes":""}]},"contexts":[{"dimension":"cross_nutrient","value_text":"Magnesium-dependent ATP chemistry is coupled to sodium and potassium handling by the pump; serum magnesium is not the enzyme-site concentration.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Human red cells and resealed ghosts; ATP/Mg loading, ouabain, sodium-24, potassium-42 and gamma-phosphorus-32 ATP.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Measured stoichiometry applies to specified ionic conditions; no Mg titration was performed.","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":"ATP turnover was directly linked to outward sodium pumping in a magnesium-containing preparation.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[garrahan-1967-nka] The stoicheiometry of the sodium pump (1967). https://doi.org/10.1113/jphysiol.1967.sp008297 DOI: 10.1113/jphysiol.1967.sp008297","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Resealed erythrocyte ghosts","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"transport_direction","value_text":"Sodium: intracellular ghost compartment to external medium.","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"c4246e36-7dcf-5581-8d4f-6a4468b9307c","evidence_kind":"source_excerpt","locator":"Lines 819-830","start_line":819,"end_line":830,"excerpt":"### mg-nka-isotope-atp-sodium-coupling\nIn Mg-loaded human red-cell ghosts, ouabain-sensitive hydrolysis of one ATP accompanied loss of about three sodium ions.\nCondition category: normal\nnutrient_topic: Magnesium research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: ATP turnover was directly linked to outward sodium pumping in a magnesium-containing preparation.\norganism: Homo sapiens\ntissue_or_cell_type: Resealed erythrocyte ghosts\nexperimental_model: Human red cells and resealed ghosts; ATP/Mg loading, ouabain, sodium-24, potassium-42 and gamma-phosphorus-32 ATP.\nlimitations: Measured stoichiometry applies to specified ionic conditions; no Mg titration was performed.\ncross_nutrient: Magnesium-dependent ATP chemistry is coupled to sodium and potassium handling by the pump; serum magnesium is not the enzyme-site concentration.\ntransport_direction: Sodium: intracellular ghost compartment to external medium.\n[garrahan-1967-nka] The stoicheiometry of the sodium pump (1967). https://doi.org/10.1113/jphysiol.1967.sp008297 DOI: 10.1113/jphysiol.1967.sp008297","model_system":"Human red cells and resealed ghosts; ATP/Mg loading, ouabain, sodium-24, potassium-42 and gamma-phosphorus-32 ATP.","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [garrahan-1967-nka] The stoicheiometry of the sodium pump (1967). https://doi.org/10.1113/jphysiol.1967.sp008297 DOI: 10.1113/jphysiol.1967.sp008297","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}