{"id":"9a2565ba-af33-5696-a5da-a8cf49b6848e","stable_key":"0f17db03-207f-5910-ac8e-13dfc2f378ce:mg-nka-free-mg-sodium-occlusion","predicate":"reduces-apparent-affinity-of","statement":"Free Mg reduced apparent sodium affinity in pig-kidney pump sodium-22 occlusion experiments.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"negative","is_public":true,"mechanism_event_id":"6def5481-cb97-56c8-beff-d68dd16bd65f","mechanism_event_label":"Magnesium can oppose sodium binding as well as support ATP chemistry.","subject":{"id":"bff427ab-35f9-59c2-bb24-fd5953bbaec2","slug":"magnesium-ion","display_name":"Mg2+","entity_type_key":"ion"},"object":{"id":"4208cee7-4e67-51f4-9c05-640eb390bfb2","slug":"sodium-pump-sodium-occlusion","display_name":"Sodium occlusion by sodium-potassium ATPase","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"6def5481-cb97-56c8-beff-d68dd16bd65f","stable_key":"0f17db03-207f-5910-ac8e-13dfc2f378ce:mg-nka-free-mg-sodium-occlusion-event","event_type":"biochemical_relationship","label":"Magnesium can oppose sodium binding as well as support ATP chemistry.","description":"Free Mg reduced apparent sodium affinity in pig-kidney pump sodium-22 occlusion experiments.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"38de8704-84db-5770-ac1d-242cd787e798","slug":"sodium-ion","display_name":"Sodium ion","entity_type_key":"ion"},"role":"tracer ion","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"27c3e7bd-c6e1-5344-8130-b231a9da2cfb","slug":"sodium-potassium-atpase","display_name":"Sodium-potassium ATPase complexes","entity_type_key":"protein_family"},"role":"enzyme","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"58b974f1-d389-5bf6-81cd-889c44442c42","slug":"atp","display_name":"ATP","entity_type_key":"small_molecule"},"role":"cycling 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":"4208cee7-4e67-51f4-9c05-640eb390bfb2","slug":"sodium-pump-sodium-occlusion","display_name":"Sodium occlusion by sodium-potassium ATPase","entity_type_key":"cellular_process"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":4,"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":"Partially purified pig-kidney pump; sodium-22 occlusion, EGCg quench-flow, ATP/Mg manipulations.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Equilibrium and Na-ATPase conditions; full Na/K exchange and systemic Mg deficiency were not tested.","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":"Sus scrofa","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"Magnesium can oppose sodium binding as well as support ATP chemistry.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[faraj-2023-nka] Measurements of Na+-occluded intermediates during the catalytic cycle of the Na+/K+-ATPase provide novel insights into the mechanism of Na+ transport (2023). https://pmc.ncbi.nlm.nih.gov/articles/PMC9860123/ DOI: 10.1016/j.jbc.2022.102811","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Kidney enzyme membrane preparation","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"6b777327-a456-5ce3-b719-6d2c924383fb","evidence_kind":"source_excerpt","locator":"Lines 857-867","start_line":857,"end_line":867,"excerpt":"### mg-nka-free-mg-sodium-occlusion\nFree Mg reduced apparent sodium affinity in pig-kidney pump sodium-22 occlusion experiments.\nCondition category: normal\nnutrient_topic: Magnesium research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Magnesium can oppose sodium binding as well as support ATP chemistry.\norganism: Sus scrofa\ntissue_or_cell_type: Kidney enzyme membrane preparation\nexperimental_model: Partially purified pig-kidney pump; sodium-22 occlusion, EGCg quench-flow, ATP/Mg manipulations.\nlimitations: Equilibrium and Na-ATPase conditions; full Na/K exchange and systemic Mg deficiency were not tested.\ncross_nutrient: Magnesium-dependent ATP chemistry is coupled to sodium and potassium handling by the pump; serum magnesium is not the enzyme-site concentration.\n[faraj-2023-nka] Measurements of Na+-occluded intermediates during the catalytic cycle of the Na+/K+-ATPase provide novel insights into the mechanism of Na+ transport (2023). https://pmc.ncbi.nlm.nih.gov/articles/PMC9860123/ DOI: 10.1016/j.jbc.2022.102811","model_system":"Partially purified pig-kidney pump; sodium-22 occlusion, EGCg quench-flow, ATP/Mg manipulations.","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [faraj-2023-nka] Measurements of Na+-occluded intermediates during the catalytic cycle of the Na+/K+-ATPase provide novel insights into the mechanism of Na+ transport (2023). https://pmc.ncbi.nlm.nih.gov/articles/PMC9860123/ DOI: 10.1016/j.jbc.2022.102811","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}