{"id":"822f5f91-6c2b-595b-b40b-4dd158cd951b","stable_key":"09b23d0d-35e2-51ff-b1aa-b4f9227e4fa2:isoleucine-acat1-chloride","predicate":"binds","statement":"Human T2 structures identified a copurified chloride ion at a high-affinity site near catalytic loops at the dimer interface.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"4696ddae-3ca4-5be6-9011-ecaf9092beb5","mechanism_event_label":"A second ion occupies a structural site in the same enzyme.","subject":{"id":"6f35aa38-f875-5759-b749-97a2f6480ff3","slug":"chloride-ion","display_name":"Chloride ion","entity_type_key":"ion"},"object":{"id":"4e3ca267-b01e-550b-aa8e-4db62e54102d","slug":"acat1","display_name":"Mitochondrial acetyl-CoA acetyltransferase / ACAT1","entity_type_key":"protein"},"evidence_count":1,"mechanism_event":{"id":"4696ddae-3ca4-5be6-9011-ecaf9092beb5","stable_key":"09b23d0d-35e2-51ff-b1aa-b4f9227e4fa2:isoleucine-acat1-chloride-event","event_type":"observed_relationship","label":"A second ion occupies a structural site in the same enzyme.","description":"Human T2 structures identified a copurified chloride ion at a high-affinity site near catalytic loops at the dimer interface.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"6f35aa38-f875-5759-b749-97a2f6480ff3","slug":"chloride-ion","display_name":"Chloride ion","entity_type_key":"ion"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"4e3ca267-b01e-550b-aa8e-4db62e54102d","slug":"acat1","display_name":"Mitochondrial acetyl-CoA acetyltransferase / ACAT1","entity_type_key":"protein"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"c85b327e-f132-5d9a-8e4b-c2976fcc0373","slug":"isoleucine","display_name":"L-Isoleucine","entity_type_key":"small_molecule"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"2c795364-e2ff-5782-8270-81e153e92c9d","slug":"2-methylacetoacetyl-coa","display_name":"2-Methylacetoacetyl-CoA","entity_type_key":"small_molecule"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""}]},"contexts":[{"dimension":"evidence_access","value_text":"Primary abstract","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Human T2 crystallography.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Binding-site evidence does not establish dietary chloride limitation or clinical repletion effects.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"L-Isoleucine collection; species, compartment, exposure, co-substrates and manipulation remain explicit.","comparator":null,"unit":null,"notes":"","entity":{"slug":"isoleucine","display_name":"L-Isoleucine","entity_type_key":"small_molecule"}},{"dimension":"plain_language","value_text":"A second ion occupies a structural site in the same enzyme.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"Crystallographic and kinetic studies of human mitochondrial acetoacetyl-CoA thiolase: the importance of potassium and chloride ions for its structure and function. · 2007 · https://pubmed.ncbi.nlm.nih.gov/17371050/ · DOI 10.1021/bi6026192","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"2d9d4748-bc61-50dc-b7ac-19b5d0aa6730","evidence_kind":"source_excerpt","locator":"Lines 242-248","start_line":242,"end_line":248,"excerpt":"## isoleucine-acat1-chloride\nA second ion occupies a structural site in the same enzyme.\nHuman T2 structures identified a copurified chloride ion at a high-affinity site near catalytic loops at the dimer interface.\nModel: Human T2 crystallography.\nLimitations: Binding-site evidence does not establish dietary chloride limitation or clinical repletion effects.\nEvidence access: Primary abstract\nCrystallographic and kinetic studies of human mitochondrial acetoacetyl-CoA thiolase: the importance of potassium and chloride ions for its structure and function. · 2007 · https://pubmed.ncbi.nlm.nih.gov/17371050/ · DOI 10.1021/bi6026192","model_system":"Human T2 crystallography.","directness":"reported_statement","verification_status":"source_derived_draft","notes":"Original curation paraphrase; 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