{"id":"6c5b4a5d-0505-5d71-aebf-6a38abf4cdbb","stable_key":"548ab9d6-3a9b-5bed-879c-17d03813b636:b2-txnrd1-fad-nadph-architecture","predicate":"binds","statement":"The rat TXNRD1 Sec498Cys structure showed conserved FAD- and NADPH-binding architecture around the N-terminal redox center.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"positive","is_public":true,"mechanism_event_id":"27be324f-a136-5b29-964a-1732e7249175","mechanism_event_label":"Thioredoxin reductase has a flavin input side.","subject":{"id":"e2cd7179-f218-54e8-9ce9-7a836ae35fac","slug":"fad","display_name":"FAD","entity_type_key":"small_molecule"},"object":{"id":"44c93642-76cb-5254-9edb-14a3020a5ae6","slug":"rat-txnrd1","display_name":"Rat thioredoxin reductase 1 / Txnrd1","entity_type_key":"protein"},"evidence_count":1,"mechanism_event":{"id":"27be324f-a136-5b29-964a-1732e7249175","stable_key":"548ab9d6-3a9b-5bed-879c-17d03813b636:b2-txnrd1-fad-nadph-architecture-event","event_type":"biochemical_relationship","label":"Thioredoxin reductase has a flavin input side.","description":"The rat TXNRD1 Sec498Cys structure showed conserved FAD- and NADPH-binding architecture around the N-terminal redox center.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"e2cd7179-f218-54e8-9ce9-7a836ae35fac","slug":"fad","display_name":"FAD","entity_type_key":"small_molecule"},"role":"cofactor","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"be6e4670-953f-5a4e-97da-1e536a54e0e4","slug":"nadp-plus","display_name":"NADP+","entity_type_key":"small_molecule"},"role":"crystallographic ligand","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"3e52ad46-1a6e-52c4-b5d6-fda4a32b8725","slug":"rat-txnrd1-sec498cys","display_name":"Rat TXNRD1 Sec498Cys protein","entity_type_key":"protein_state"},"role":"crystallized protein","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"44c93642-76cb-5254-9edb-14a3020a5ae6","slug":"rat-txnrd1","display_name":"Rat thioredoxin reductase 1 / Txnrd1","entity_type_key":"protein"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""}]},"contexts":[{"dimension":"cross_nutrient","value_text":"B2-FAD and nicotinamide cofactors provide the upstream side of a selenium-containing reductase.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"evidence_location","value_text":"Abstract","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Rat TXNRD1 Sec498Cys recombinant mutant with NADP+, 3.0-A crystallography and substrate-docking interpretation.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"Purified-enzyme assay","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Structure used a Sec-to-Cys mutant and oxidized NADP+; direct atom-level conclusions about wild-type selenium chemistry are limited.","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":"Rattus norvegicus protein expressed recombinantly","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"Thioredoxin reductase has a flavin input side.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[sandalova2001] Three-dimensional structure of a mammalian thioredoxin reductase: implications for mechanism and evolution of a selenocysteine-dependent enzyme. (2001). https://pubmed.ncbi.nlm.nih.gov/11481439/ DOI: 10.1073/pnas.171178698","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Purified recombinant enzyme; no intact tissue","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"1f5cd8a3-16f6-5b43-be3a-f931cb28a459","evidence_kind":"source_excerpt","locator":"Lines 1346-1358","start_line":1346,"end_line":1358,"excerpt":"### b2-txnrd1-fad-nadph-architecture\nThe rat TXNRD1 Sec498Cys structure showed conserved FAD- and NADPH-binding architecture around the N-terminal redox center.\nCondition category: normal\nnutrient_topic: Riboflavin research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Thioredoxin reductase has a flavin input side.\norganism: Rattus norvegicus protein expressed recombinantly\ntissue_or_cell_type: Purified recombinant enzyme; no intact tissue\nexperimental_model: Rat TXNRD1 Sec498Cys recombinant mutant with NADP+, 3.0-A crystallography and substrate-docking interpretation.\nlimitations: Structure used a Sec-to-Cys mutant and oxidized NADP+; direct atom-level conclusions about wild-type selenium chemistry are limited.\nexposure: Purified-enzyme assay\ncross_nutrient: B2-FAD and nicotinamide cofactors provide the upstream side of a selenium-containing reductase.\nevidence_location: Abstract\n[sandalova2001] Three-dimensional structure of a mammalian thioredoxin reductase: implications for mechanism and evolution of a selenocysteine-dependent enzyme. (2001). https://pubmed.ncbi.nlm.nih.gov/11481439/ DOI: 10.1073/pnas.171178698","model_system":"Rat TXNRD1 Sec498Cys recombinant mutant with NADP+, 3.0-A crystallography and substrate-docking interpretation.","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [sandalova2001] Three-dimensional structure of a mammalian thioredoxin reductase: implications for mechanism and evolution of a selenocysteine-dependent enzyme. 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