{"id":"32f56aa0-34ed-58b5-b1be-ddc569d2ff05","stable_key":"aaa7baba-8689-56ab-ba1e-b71542bcb8e9:iodine-syn-iyd-fmn-binding","predicate":"binds","statement":"Human IYD crystal structures show one bound FMN per polypeptide, with iodotyrosine contacting its isoalloxazine ring in the substrate complex.","claim_class":"identity","status":"source_derived_draft","evidence_grade":"ungraded","direction":"positive","is_public":true,"mechanism_event_id":"871416ee-efab-5c95-8df6-f767542f2d7d","mechanism_event_label":"IYD uses the vitamin-B2-derived cofactor FMN to handle iodotyrosine.","subject":{"id":"10765e77-4f0b-5789-81c0-3ce11c80d583","slug":"human-iyd-delta-anchor","display_name":"Human IYD lacking N-terminal membrane anchor","entity_type_key":"protein_state"},"object":{"id":"d3eacf85-1a35-546d-bd30-161474dd9691","slug":"fmn","display_name":"Flavin mononucleotide","entity_type_key":"small_molecule"},"evidence_count":1,"mechanism_event":{"id":"871416ee-efab-5c95-8df6-f767542f2d7d","stable_key":"aaa7baba-8689-56ab-ba1e-b71542bcb8e9:iodine-syn-iyd-fmn-binding-event","event_type":"biochemical_relationship","label":"IYD uses the vitamin-B2-derived cofactor FMN to handle iodotyrosine.","description":"Human IYD crystal structures show one bound FMN per polypeptide, with iodotyrosine contacting its isoalloxazine ring in the substrate complex.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"50a4f425-207d-55ec-b73e-3e93e7c2695e","slug":"iyd","display_name":"Human iodotyrosine deiodinase","entity_type_key":"protein"},"role":"full_length_parent","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"c88508eb-a2ea-56bb-9e69-48fde635fb7f","slug":"monoiodotyrosine","display_name":"3-Iodo-L-tyrosine","entity_type_key":"small_molecule"},"role":"bound_substrate","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"86eb1eee-a8d1-539c-8c17-0911f69b6f1b","slug":"riboflavin","display_name":"Riboflavin (vitamin B2)","entity_type_key":"small_molecule"},"role":"FMN_vitamin_precursor","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"10765e77-4f0b-5789-81c0-3ce11c80d583","slug":"human-iyd-delta-anchor","display_name":"Human IYD lacking N-terminal membrane anchor","entity_type_key":"protein_state"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""},{"entity":{"id":"d3eacf85-1a35-546d-bd30-161474dd9691","slug":"fmn","display_name":"Flavin mononucleotide","entity_type_key":"small_molecule"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":4,"notes":""}]},"contexts":[{"dimension":"cross_nutrient","value_text":"true","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"evidence_span","value_text":"{\"source_cache\": \"artifacts/iodine-synthesis-sources/25395621.txt\", \"start_char\": 14596, \"end_char\": 15366, \"text_sha256\": \"5f3959109e358adaddae3ea78c716d16316c28f6fb4153ad5696bae7b1ed733e\", \"text_characters\": 770, \"note\": \"Exact publisher passage retained in the cited local source cache; locator and digest supplied here.\"}","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Recombinant human IYD lacking residues 1–31; crystallography, radiotracer kinetics and redox titration","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"Human soluble IYD crystallized alone or with 3-iodo-L-tyrosine.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Cofactor structure; no riboflavin restriction or supplementation study.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Iodine research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"iodine","display_name":"Iodine","entity_type_key":"nutrient_element"}},{"dimension":"organism","value_text":"Homo sapiens recombinant protein","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"IYD uses the vitamin-B2-derived cofactor FMN to handle iodotyrosine.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[iodine-syn-iyd2015] A switch between one- and two-electron chemistry of the human flavoprotein iodotyrosine deiodinase is controlled by substrate. (2015). https://pubmed.ncbi.nlm.nih.gov/25395621/ DOI: 10.1074/jbc.m114.605964","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Purified soluble IYD","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"241969e7-5a64-5d0b-b343-26afff5f3d7d","evidence_kind":"source_excerpt","locator":"Lines 702-714","start_line":702,"end_line":714,"excerpt":"### iodine-syn-iyd-fmn-binding\nHuman IYD crystal structures show one bound FMN per polypeptide, with iodotyrosine contacting its isoalloxazine ring in the substrate complex.\nCondition category: normal\nnutrient_topic: Iodine research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: IYD uses the vitamin-B2-derived cofactor FMN to handle iodotyrosine.\norganism: Homo sapiens recombinant protein\ntissue_or_cell_type: Purified soluble IYD\nexperimental_model: Recombinant human IYD lacking residues 1–31; crystallography, radiotracer kinetics and redox titration\nlimitations: Cofactor structure; no riboflavin restriction or supplementation study.\nexposure: Human soluble IYD crystallized alone or with 3-iodo-L-tyrosine.\ncross_nutrient: true\nevidence_span: {\"source_cache\": \"artifacts/iodine-synthesis-sources/25395621.txt\", \"start_char\": 14596, \"end_char\": 15366, \"text_sha256\": \"5f3959109e358adaddae3ea78c716d16316c28f6fb4153ad5696bae7b1ed733e\", \"text_characters\": 770, \"note\": \"Exact publisher passage retained in the cited local source cache; locator and digest supplied here.\"}\n[iodine-syn-iyd2015] A switch between one- and two-electron chemistry of the human flavoprotein iodotyrosine deiodinase is controlled by substrate. (2015). https://pubmed.ncbi.nlm.nih.gov/25395621/ DOI: 10.1074/jbc.m114.605964","model_system":"Recombinant human IYD lacking residues 1–31; crystallography, radiotracer kinetics and redox titration","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [iodine-syn-iyd2015] A switch between one- and two-electron chemistry of the human flavoprotein iodotyrosine deiodinase is controlled by substrate. 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