{"id":"606d0316-5ee9-5d3a-92ab-f4165394559a","stable_key":"548ab9d6-3a9b-5bed-879c-17d03813b636:b2-met-mcad-etf-interface","predicate":"uses-specific-interface-for-transfer","statement":"Interface mutagenesis and solution electron-transfer measurements supported a role for MCAD Glu212 and ETF alpha Arg249 interactions in productive electron transfer.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"positive","is_public":true,"mechanism_event_id":"dfc24d3f-67f5-5703-8039-649ddbb4b2a2","mechanism_event_label":"Correct contact between the proteins matters as well as having the cofactor.","subject":{"id":"22d58f68-4758-52a6-9127-70a32ca264cc","slug":"acadm","display_name":"Human medium-chain acyl-CoA dehydrogenase / ACADM","entity_type_key":"protein"},"object":{"id":"949ab4a0-5377-5106-9ca4-6077d83bf31b","slug":"etfa","display_name":"Human electron transfer flavoprotein alpha / ETFA","entity_type_key":"protein"},"evidence_count":1,"mechanism_event":{"id":"dfc24d3f-67f5-5703-8039-649ddbb4b2a2","stable_key":"548ab9d6-3a9b-5bed-879c-17d03813b636:b2-met-mcad-etf-interface-event","event_type":"biochemical_relationship","label":"Correct contact between the proteins matters as well as having the cofactor.","description":"Interface mutagenesis and solution electron-transfer measurements supported a role for MCAD Glu212 and ETF alpha Arg249 interactions in productive electron transfer.","status":"provisional","compartment":{"slug":"mitochondria","display_name":"Mitochondria"},"participants":[{"entity":{"id":"8851f7f6-96e8-534d-ba5f-d3eab68eb3db","slug":"electron-transfer-flavoprotein","display_name":"Human electron transfer flavoprotein / ETF","entity_type_key":"protein_complex"},"role":"acceptor complex","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"e2cd7179-f218-54e8-9ce9-7a836ae35fac","slug":"fad","display_name":"FAD","entity_type_key":"small_molecule"},"role":"redox cofactor","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"22d58f68-4758-52a6-9127-70a32ca264cc","slug":"acadm","display_name":"Human medium-chain acyl-CoA dehydrogenase / ACADM","entity_type_key":"protein"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"949ab4a0-5377-5106-9ca4-6077d83bf31b","slug":"etfa","display_name":"Human electron transfer flavoprotein alpha / ETFA","entity_type_key":"protein"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""}]},"contexts":[{"dimension":"evidence_spans","value_text":"[{\"source_bundle\": \"artifacts/riboflavin_metabolism_sources.json\", \"source_key\": \"PMID15159392\", \"locator\": \"metadata.abstractText\", \"paragraph_index\": 0, \"char_start\": 0, \"char_end\": 1430, \"evidence_access\": \"primary-abstract\"}]","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Human ETF-MCAD complex crystallography and solution interfacial mutagenesis.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"No nutrient intervention; 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topical membership is not evidence of a direct dietary effect.\nplain_language: Correct contact between the proteins matters as well as having the cofactor.\norganism: Homo sapiens\ntissue_or_cell_type: Recombinant protein interaction assays\nexperimental_model: Human ETF-MCAD complex crystallography and solution interfacial mutagenesis.\nlimitations: Residue interactions were inferred from combined structural/kinetic evidence; this is not a dietary-deficiency experiment.\nexposure: No nutrient intervention; structural or biochemical characterization.\nevidence_spans: [{\"source_bundle\": \"artifacts/riboflavin_metabolism_sources.json\", \"source_key\": \"PMID15159392\", \"locator\": \"metadata.abstractText\", \"paragraph_index\": 0, \"char_start\": 0, \"char_end\": 1430, \"evidence_access\": \"primary-abstract\"}]\n[toogood-2004-etf-mcad] Extensive domain motion and electron transfer in the human electron transferring flavoprotein.medium chain Acyl-CoA dehydrogenase complex (2004). https://pubmed.ncbi.nlm.nih.gov/15159392/ DOI: 10.1074/jbc.m404884200","model_system":"Human ETF-MCAD complex crystallography and solution interfacial mutagenesis.","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [toogood-2004-etf-mcad] Extensive domain motion and electron transfer in the human electron transferring flavoprotein.medium chain Acyl-CoA dehydrogenase complex (2004). https://pubmed.ncbi.nlm.nih.gov/15159392/ DOI: 10.1074/jbc.m404884200","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"4f7c9578-82bf-5e2d-b5c4-72a79fb4f6af","stable_key":"import-548ab9d6-3a9b-5bed-879c-17d03813b636","title":"Riboflavin: mechanisms, deficiency and nutrient interactions (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":"680cb6bc8249877f2410f551807f10d390fdd719014137d7414ba3420e29228d","revision_id":"7a61e299-908d-5372-860b-99ed190f9d7a","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}