{"id":"fbf3b9d6-0c5a-52d8-8a02-f24c65a42562","stable_key":"09b23d0d-35e2-51ff-b1aa-b4f9227e4fa2:isoleucine-bcat-reaction","predicate":"transaminates","statement":"Human BCAT2 transfers the isoleucine amino group through the PLP/PMP cycle, linking isoleucine/branched ketoacid interconversion to 2-oxoglutarate/glutamate.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"682e24b0-aeac-5853-927f-a76ff689c648","mechanism_event_label":"The first breakdown step passes nitrogen to another metabolite.","subject":{"id":"078444ed-0927-573a-b54d-5fdabb5d04ae","slug":"bcat2","display_name":"Human mitochondrial branched-chain aminotransferase / BCAT2","entity_type_key":"protein"},"object":{"id":"10548a8b-eb7a-57fe-b86a-05e699591156","slug":"alpha-keto-beta-methylvalerate","display_name":"3-Methyl-2-oxopentanoate","entity_type_key":"small_molecule"},"evidence_count":1,"mechanism_event":{"id":"682e24b0-aeac-5853-927f-a76ff689c648","stable_key":"09b23d0d-35e2-51ff-b1aa-b4f9227e4fa2:isoleucine-bcat-reaction-event","event_type":"observed_relationship","label":"The first breakdown step passes nitrogen to another metabolite.","description":"Human BCAT2 transfers the isoleucine amino group through the PLP/PMP cycle, linking isoleucine/branched ketoacid interconversion to 2-oxoglutarate/glutamate.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"078444ed-0927-573a-b54d-5fdabb5d04ae","slug":"bcat2","display_name":"Human mitochondrial branched-chain aminotransferase / BCAT2","entity_type_key":"protein"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"10548a8b-eb7a-57fe-b86a-05e699591156","slug":"alpha-keto-beta-methylvalerate","display_name":"3-Methyl-2-oxopentanoate","entity_type_key":"small_molecule"},"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":"6b656ff5-9532-5da4-8eea-8ca163a48649","slug":"pyridoxal-phosphate","display_name":"PLP","entity_type_key":"small_molecule"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""},{"entity":{"id":"628ddc2d-e4d9-59c7-ae76-0c0cab80a6b1","slug":"2-oxoglutarate","display_name":"2-Oxoglutarate","entity_type_key":"small_molecule"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":4,"notes":""},{"entity":{"id":"7da684a4-2641-5bc6-93ae-8c6aa384e487","slug":"glutamate","display_name":"L-Glutamate","entity_type_key":"small_molecule"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":5,"notes":""}]},"contexts":[{"dimension":"evidence_access","value_text":"Primary abstract; reaction-intermediate structural study","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Human BCAT2 intermediate structures and established reaction chemistry.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Reversible enzyme chemistry; concentration and compartment determine net flux.","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":"The first breakdown step passes nitrogen to another metabolite.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"Crystal structures of human mitochondrial branched chain aminotransferase reaction intermediates: ketimine and pyridoxamine phosphate forms. · 2002 · https://pubmed.ncbi.nlm.nih.gov/12269802/ · DOI 10.1021/bi020221c","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"1b45e8a7-bb4d-5417-be81-fd15370f68a2","evidence_kind":"source_excerpt","locator":"Lines 162-168","start_line":162,"end_line":168,"excerpt":"## isoleucine-bcat-reaction\nThe first breakdown step passes nitrogen to another metabolite.\nHuman BCAT2 transfers the isoleucine amino group through the PLP/PMP cycle, linking isoleucine/branched ketoacid interconversion to 2-oxoglutarate/glutamate.\nModel: Human BCAT2 intermediate structures and established reaction chemistry.\nLimitations: Reversible enzyme chemistry; concentration and compartment determine net flux.\nEvidence access: Primary abstract; reaction-intermediate structural study\nCrystal structures of human mitochondrial branched chain aminotransferase reaction intermediates: ketimine and pyridoxamine phosphate forms. · 2002 · https://pubmed.ncbi.nlm.nih.gov/12269802/ · DOI 10.1021/bi020221c","model_system":"Human BCAT2 intermediate structures and established reaction chemistry.","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":"4b00f118-00fd-5cef-be97-13125eb958e9","stable_key":"import-09b23d0d-35e2-51ff-b1aa-b4f9227e4fa2","title":"L-Isoleucine: transport, translation, catabolism 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":"2058ff0da379586994e7fda6ae0086c60fa3173542bfaf1fb3871ad3e09f9c6c","revision_id":"f32192d4-9913-5d35-acbc-cf90ff17995e","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}