{"id":"d2b922c5-21f1-503e-b8d8-703d783e0c8f","stable_key":"548ab9d6-3a9b-5bed-879c-17d03813b636:b2-kmo-loss-quinolinate-tissue","predicate":"supports-production-of","statement":"Kmo knockout reduced quinolinate to about 3% of wild-type liver content but about 80% of wild-type brain content.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"f252f509-dbab-5d68-94c0-337b8b5212c3","mechanism_event_label":"Removing this enzyme affected downstream metabolites differently across tissues.","subject":{"id":"41e2c985-04a2-503e-a39a-91bdcc0403f3","slug":"mouse-kmo","display_name":"Mouse kynurenine 3-monooxygenase / Kmo","entity_type_key":"protein"},"object":{"id":"ab444b3c-c8ec-5ada-8450-36ac9934d6b6","slug":"quinolinic-acid","display_name":"Quinolinic acid","entity_type_key":"small_molecule"},"evidence_count":1,"mechanism_event":{"id":"f252f509-dbab-5d68-94c0-337b8b5212c3","stable_key":"548ab9d6-3a9b-5bed-879c-17d03813b636:b2-kmo-loss-quinolinate-tissue-event","event_type":"biochemical_relationship","label":"Removing this enzyme affected downstream metabolites differently across tissues.","description":"Kmo knockout reduced quinolinate to about 3% of wild-type liver content but about 80% of wild-type brain content.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"ab444b3c-c8ec-5ada-8450-36ac9934d6b6","slug":"quinolinic-acid","display_name":"Quinolinic acid","entity_type_key":"small_molecule"},"role":"downstream metabolite","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"215d55a2-1657-589c-aaf4-afd1957859e7","slug":"3-hydroxykynurenine","display_name":"3-Hydroxy-L-kynurenine","entity_type_key":"small_molecule"},"role":"intermediate","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"41e2c985-04a2-503e-a39a-91bdcc0403f3","slug":"mouse-kmo","display_name":"Mouse kynurenine 3-monooxygenase / Kmo","entity_type_key":"protein"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""}]},"contexts":[{"dimension":"availability_state","value_text":"machinery_impairment","comparator":null,"unit":null,"notes":"Imported condition classification; unverified.","entity":null},{"dimension":"cross_nutrient","value_text":"A B2-dependent step feeds the tryptophan-to-niacin pathway with tissue-specific dependence.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"evidence_location","value_text":"Results: liver Fig 4 and brain Fig 7; matching abstract conclusion","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Constitutive Kmo knockout and wild-type mice, approximately two months old; liver and brain metabolite assays.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"Constitutive Kmo deletion","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Genetic deletion; alternative routes were proposed but not all directly traced.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Riboflavin research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"riboflavin","display_name":"Riboflavin (vitamin B2)","entity_type_key":"small_molecule"}},{"dimension":"organism","value_text":"Mus musculus","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"Removing this enzyme affected downstream metabolites differently across tissues.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[giorgini2013] Targeted deletion of kynurenine 3-monooxygenase in mice: a new tool for studying kynurenine pathway metabolism in periphery and brain. (2013). https://pubmed.ncbi.nlm.nih.gov/24189070/ DOI: 10.1074/jbc.m113.503813","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Liver and brain","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"trigger_kind","value_text":"machinery_impairment","comparator":null,"unit":null,"notes":"Imported condition classification; unverified.","entity":null}],"evidence":[{"id":"9abd2e2f-fdd0-5c11-9d65-63993ed89823","evidence_kind":"source_excerpt","locator":"Lines 1248-1260","start_line":1248,"end_line":1260,"excerpt":"### b2-kmo-loss-quinolinate-tissue\nKmo knockout reduced quinolinate to about 3% of wild-type liver content but about 80% of wild-type brain content.\nCondition category: machinery_impairment\nnutrient_topic: Riboflavin research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Removing this enzyme affected downstream metabolites differently across tissues.\norganism: Mus musculus\ntissue_or_cell_type: Liver and brain\nexperimental_model: Constitutive Kmo knockout and wild-type mice, approximately two months old; liver and brain metabolite assays.\nlimitations: Genetic deletion; alternative routes were proposed but not all directly traced.\nexposure: Constitutive Kmo deletion\ncross_nutrient: A B2-dependent step feeds the tryptophan-to-niacin pathway with tissue-specific dependence.\nevidence_location: Results: liver Fig 4 and brain Fig 7; matching abstract conclusion\n[giorgini2013] Targeted deletion of kynurenine 3-monooxygenase in mice: a new tool for studying kynurenine pathway metabolism in periphery and brain. (2013). https://pubmed.ncbi.nlm.nih.gov/24189070/ DOI: 10.1074/jbc.m113.503813","model_system":"Constitutive Kmo knockout and wild-type mice, approximately two months old; liver and brain metabolite assays.","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [giorgini2013] Targeted deletion of kynurenine 3-monooxygenase in mice: a new tool for studying kynurenine pathway metabolism in periphery and brain. (2013). https://pubmed.ncbi.nlm.nih.gov/24189070/ DOI: 10.1074/jbc.m113.503813","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}