{"id":"b6605dbc-466c-5591-965b-0a11b1b3c6fc","stable_key":"research:scly-decomposes-selenocysteine","predicate":"decomposes","statement":"SCLY decomposes free L-selenocysteine, yielding L-alanine and released selenium.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"literature_reviewed:direct_experimental","direction":"neutral","is_public":true,"mechanism_event_id":"1c7e28b3-1cce-5027-9d28-cb17d1eeeab2","mechanism_event_label":"SCLY recovers selenium from free selenocysteine.","subject":{"id":"7c1bfe9f-559b-598e-9cca-8d0b032919fd","slug":"scly","display_name":"SCLY","entity_type_key":"protein"},"object":{"id":"533add43-f6ba-5428-ab2d-74a45c054655","slug":"selenocysteine","display_name":"Sec","entity_type_key":"small_molecule"},"evidence_count":1,"mechanism_event":{"id":"1c7e28b3-1cce-5027-9d28-cb17d1eeeab2","stable_key":"research:scly-decomposes-selenocysteine","event_type":"catalysis","label":"SCLY recovers selenium from free selenocysteine.","description":"SCLY decomposes free L-selenocysteine, yielding L-alanine and released selenium.","status":"active","compartment":null,"participants":[{"entity":{"id":"7c1bfe9f-559b-598e-9cca-8d0b032919fd","slug":"scly","display_name":"SCLY","entity_type_key":"protein"},"role":"enzyme","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"533add43-f6ba-5428-ab2d-74a45c054655","slug":"selenocysteine","display_name":"Sec","entity_type_key":"small_molecule"},"role":"substrate","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"ebdc4461-c059-563e-88b0-422c21fdaa25","slug":"alanine","display_name":"L-Alanine","entity_type_key":"small_molecule"},"role":"product","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"dc89d7e2-8f89-577b-838f-42bf5d8ec7c8","slug":"selenium","display_name":"Selenium","entity_type_key":"nutrient_element"},"role":"product","stoichiometry":null,"state_label":"released; intracellular chemical species not assigned","sequence_order":3,"notes":""},{"entity":{"id":"6b656ff5-9532-5da4-8eea-8ca163a48649","slug":"pyridoxal-phosphate","display_name":"PLP","entity_type_key":"small_molecule"},"role":"cofactor","stoichiometry":null,"state_label":"","sequence_order":4,"notes":""}]},"contexts":[{"dimension":"cell_type","value_text":"liver-derived enzyme","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Purified and recombinant enzyme","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"The original assay described elemental selenium; intracellular speciation remains separate.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"organism","value_text":"mouse","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"531da44e-e207-53d0-b01d-48d2546d9a20","evidence_kind":"curated_literature_summary","locator":"lines 510-520","start_line":510,"end_line":520,"excerpt":"## scly-decomposes-selenocysteine\n\nSCLY recovers selenium from free selenocysteine.\n\nSCLY decomposes free L-selenocysteine, yielding L-alanine and released selenium.\n\nOrganism: mouse\nCell type: liver-derived enzyme\nExperimental model: Purified and recombinant enzyme\nLimitations: The original assay described elemental selenium; intracellular speciation remains separate.\nPrimary reference: [cDNA cloning, purification, and characterization of mouse liver selenocysteine lyase. Candidate for selenium delivery protein in selenoprotein synthesis](https://pubmed.ncbi.nlm.nih.gov/10692412/)","model_system":"Purified and recombinant enzyme","directness":"author_interpretation","verification_status":"secondary_verified","notes":"Curated summary; inspect the linked primary papers for original methods and results.","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"4f892f13-06ea-5199-a33c-a703f35c80ae","stable_key":"selenium-research-2026-09-17","title":"Selenium: literature corrections and mechanism additions","document_type":"curated_literature_review","citation_label":"Metabolic Ledger literature curation, 17 September 2026; primary papers linked individually","file_path":"","sha256":"0b818b10c1c7120e5caf7f4d4019d7bd025d745692e424f515d3ef903c9ab7f3","revision_id":"80984e03-5f0f-5877-8094-afef7637444e","review_status":"secondary_verified","notes":"Secondary curated summaries of primary experiments, with explicit models and limitations. Not archived primary full text."}}],"relations":[],"conflicts":[],"corrections":[],"research":{"topic":"selenium-recycling","plain_language":"SCLY recovers selenium from free selenocysteine.","evidence_scope":"direct_experimental","papers":[{"key":"mihara-2000-scly","title":"cDNA cloning, purification, and characterization of mouse liver selenocysteine lyase. Candidate for selenium delivery protein in selenoprotein synthesis","url":"https://pubmed.ncbi.nlm.nih.gov/10692412/","doi":"10.1074/jbc.275.9.6195","year":2000,"model":"Purified mouse liver enzyme and recombinant characterization","summary":"Characterizes PLP-dependent selenocysteine decomposition by mammalian SCLY."}]}}