{"id":"98fd9ee6-ac32-58c4-8fee-da2468a0d894","stable_key":"63ce713e-6aea-59f6-9896-ca30e010b2ce:l-tyrosine-gst-isomerase","predicate":"produces","statement":"Human GSTZ1/MAAI catalyzes glutathione-dependent isomerization of maleylacetoacetate to fumarylacetoacetate.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"3d38a170-b572-580e-9cad-88bb2a32a679","mechanism_event_label":"Glutathione has a catalytic role in nutrient breakdown as well as antioxidant roles.","subject":{"id":"098eb575-0232-50d0-8620-bfabc07eadea","slug":"gstz1","display_name":"Human maleylacetoacetate isomerase / GSTZ1","entity_type_key":"protein"},"object":{"id":"ef632139-c932-5dab-ae28-4bffb9f50bd6","slug":"fumarylacetoacetate","display_name":"Fumarylacetoacetate","entity_type_key":"small_molecule"},"evidence_count":1,"mechanism_event":{"id":"3d38a170-b572-580e-9cad-88bb2a32a679","stable_key":"63ce713e-6aea-59f6-9896-ca30e010b2ce:l-tyrosine-gst-isomerase-event","event_type":"observed_relationship","label":"Glutathione has a catalytic role in nutrient breakdown as well as antioxidant roles.","description":"Human GSTZ1/MAAI catalyzes glutathione-dependent isomerization of maleylacetoacetate to fumarylacetoacetate.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"098eb575-0232-50d0-8620-bfabc07eadea","slug":"gstz1","display_name":"Human maleylacetoacetate isomerase / GSTZ1","entity_type_key":"protein"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"ef632139-c932-5dab-ae28-4bffb9f50bd6","slug":"fumarylacetoacetate","display_name":"Fumarylacetoacetate","entity_type_key":"small_molecule"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"bcfef85f-831d-5439-ba51-1aef4b090441","slug":"l-tyrosine","display_name":"L-Tyrosine","entity_type_key":"small_molecule"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"a4a0785d-bd5f-56e3-ad95-8c1ceff53bfa","slug":"maleylacetoacetate","display_name":"Maleylacetoacetate","entity_type_key":"small_molecule"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""},{"entity":{"id":"b44c9e27-4bbb-52d3-a022-14cddded5073","slug":"glutathione","display_name":"GSH","entity_type_key":"small_molecule"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":4,"notes":""}]},"contexts":[{"dimension":"evidence_access","value_text":"Primary abstract","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Human MAAI crystal structure with glutathione and a substrate-mimicking sulfate ion.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Glutathione dependence does not imply stoichiometric depletion by ordinary tyrosine intake.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"L-Tyrosine collection; species, compartment, exposure, co-substrates and manipulation remain explicit.","comparator":null,"unit":null,"notes":"","entity":{"slug":"l-tyrosine","display_name":"L-Tyrosine","entity_type_key":"small_molecule"}},{"dimension":"plain_language","value_text":"Glutathione has a catalytic role in nutrient breakdown as well as antioxidant roles.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"Crystal structure of maleylacetoacetate isomerase/glutathione transferase zeta reveals the molecular basis for its remarkable catalytic promiscuity. · 2001 · https://pubmed.ncbi.nlm.nih.gov/11327815/ · DOI 10.1021/bi002249z","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"fc323772-3262-5916-b1f4-617fa96615b9","evidence_kind":"source_excerpt","locator":"Lines 252-258","start_line":252,"end_line":258,"excerpt":"## l-tyrosine-gst-isomerase\nGlutathione has a catalytic role in nutrient breakdown as well as antioxidant roles.\nHuman GSTZ1/MAAI catalyzes glutathione-dependent isomerization of maleylacetoacetate to fumarylacetoacetate.\nModel: Human MAAI crystal structure with glutathione and a substrate-mimicking sulfate ion.\nLimitations: Glutathione dependence does not imply stoichiometric depletion by ordinary tyrosine intake.\nEvidence access: Primary abstract\nCrystal structure of maleylacetoacetate isomerase/glutathione transferase zeta reveals the molecular basis for its remarkable catalytic promiscuity. · 2001 · https://pubmed.ncbi.nlm.nih.gov/11327815/ · DOI 10.1021/bi002249z","model_system":"Human MAAI crystal structure with glutathione and a substrate-mimicking sulfate ion.","directness":"reported_statement","verification_status":"source_derived_draft","notes":"Original curation paraphrase; evidence access and experimental limitations specified.","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"12917df2-c6e0-5b61-850f-dbff6d4b4d30","stable_key":"import-63ce713e-6aea-59f6-9896-ca30e010b2ce","title":"L-Tyrosine: catecholamines, thyroid chemistry, pigment, metabolism and cross-nutrient mechanisms (2026-09-19)","document_type":"imported_text","citation_label":"AI-assisted research curation; primary references, access levels and experimental limitations individually identified. Not publisher full text.","file_path":"","sha256":"7777f4440a8bfb14a04ff73e73392ccc45d8ee89f7853ecbcc0027d6f563b8a0","revision_id":"e1206111-3a75-5809-b8e9-231ff809ff1e","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}