{"id":"60d58451-0c52-53e9-b25a-efc5af9fb80f","stable_key":"335be270-ea4a-5c8e-ad04-964fd22a439e:vanadium-pump-potassium","predicate":"increases_vanadate_binding","statement":"In magnesium-containing medium, potassium increased vanadate binding and lowered its Kd to about 11 nM without changing maximum binding.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"59e10567-982f-557a-8438-3cccf32380d3","mechanism_event_label":"Potassium can shift the pump toward an inhibitor-sensitive state.","subject":{"id":"5dd31e52-f51e-51f3-880e-240abcc0ab1d","slug":"potassium-ion","display_name":"Potassium ion","entity_type_key":"ion"},"object":{"id":"4d1e42e4-30e4-53aa-b967-9a8e2ed3043a","slug":"dog-kidney-na-k-atpase","display_name":"Dog kidney sodium/potassium ATPase preparation","entity_type_key":"protein_complex"},"evidence_count":1,"mechanism_event":{"id":"59e10567-982f-557a-8438-3cccf32380d3","stable_key":"335be270-ea4a-5c8e-ad04-964fd22a439e:vanadium-pump-potassium-event","event_type":"observed_relationship","label":"Potassium can shift the pump toward an inhibitor-sensitive state.","description":"In magnesium-containing medium, potassium increased vanadate binding and lowered its Kd to about 11 nM without changing maximum binding.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"5dd31e52-f51e-51f3-880e-240abcc0ab1d","slug":"potassium-ion","display_name":"Potassium ion","entity_type_key":"ion"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"4d1e42e4-30e4-53aa-b967-9a8e2ed3043a","slug":"dog-kidney-na-k-atpase","display_name":"Dog kidney sodium/potassium ATPase preparation","entity_type_key":"protein_complex"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"c5cbad45-22c6-594b-ab6b-71880dab1b24","slug":"vanadium","display_name":"Vanadium","entity_type_key":"nutrient_element"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"bef86a6e-28a0-5df9-9306-3f05991aa159","slug":"vanadate-v","display_name":"Vanadate(V), protonation/speciation dependent","entity_type_key":"chemical_species"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""},{"entity":{"id":"bff427ab-35f9-59c2-bb24-fd5953bbaec2","slug":"magnesium-ion","display_name":"Mg2+","entity_type_key":"ion"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":4,"notes":""},{"entity":{"id":"a8082b11-c484-5792-bb81-48e8e699cbe4","slug":"manganese-ion","display_name":"Mn2+","entity_type_key":"ion"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":5,"notes":""}]},"contexts":[{"dimension":"evidence_access","value_text":"Primary abstract","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Dog kidney Na/K-ATPase binding experiments.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Effect was not appreciable under the manganese condition; not evidence that dietary potassium necessarily increases toxicity.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Vanadium collection; molecular form, preparation, species, exposure and manipulation remain explicit.","comparator":null,"unit":null,"notes":"","entity":{"slug":"vanadium","display_name":"Vanadium","entity_type_key":"nutrient_element"}},{"dimension":"plain_language","value_text":"Potassium can shift the pump toward an inhibitor-sensitive state.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"Vanadate binding to the (Na + K)-ATPase. · 1981 · https://pubmed.ncbi.nlm.nih.gov/6277881/ · DOI 10.1007/BF00743200","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"8c24bff7-d3bc-56b2-a867-0eb9bf6166b8","evidence_kind":"source_excerpt","locator":"Lines 238-244","start_line":238,"end_line":244,"excerpt":"## vanadium-pump-potassium\nPotassium can shift the pump toward an inhibitor-sensitive state.\nIn magnesium-containing medium, potassium increased vanadate binding and lowered its Kd to about 11 nM without changing maximum binding.\nModel: Dog kidney Na/K-ATPase binding experiments.\nLimitations: Effect was not appreciable under the manganese condition; not evidence that dietary potassium necessarily increases toxicity.\nEvidence access: Primary abstract\nVanadate binding to the (Na + K)-ATPase. · 1981 · https://pubmed.ncbi.nlm.nih.gov/6277881/ · DOI 10.1007/BF00743200","model_system":"Dog kidney Na/K-ATPase binding experiments.","directness":"reported_statement","verification_status":"source_derived_draft","notes":"Original curation paraphrase; evidence access and experimental limitations specified.","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"e4d5d0ba-529b-540f-96ed-e719d116ccfd","stable_key":"import-335be270-ea4a-5c8e-ad04-964fd22a439e","title":"Vanadium: speciation, phosphate-sensitive enzymes and cross-nutrient mechanisms (2026-09-19)","document_type":"imported_text","citation_label":"AI-assisted research curation; primary references, access levels and experimental limitations individually identified. Not publisher full text.","file_path":"","sha256":"d36b30d972e756ca4d19b66f976980e206c65025bd4bbf4c127c17320bd019c2","revision_id":"70d42967-8032-5627-8670-f59841735e89","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}