{"id":"d216e191-a493-5d23-9086-cb62dbce7113","stable_key":"31b1baa4-4113-5541-b9e7-fe44a5253a07:chorismate-l-tyrosine","predicate":"reported_relationship","statement":"Chorismate supplies a multistep E. coli biosynthetic branch toward l-tyrosine.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"neutral","is_public":true,"mechanism_event_id":"c5c08b49-88d3-54e9-8a0a-e2b9a19912ea","mechanism_event_label":"Chorismate supplies a multistep E. coli biosynthetic branch toward l-tyrosine.","subject":{"id":"849c016e-9dc8-567c-81b5-c8434c558a5f","slug":"chorismate","display_name":"Chorismate","entity_type_key":"small_molecule"},"object":{"id":"bcfef85f-831d-5439-ba51-1aef4b090441","slug":"l-tyrosine","display_name":"L-Tyrosine","entity_type_key":"small_molecule"},"evidence_count":1,"mechanism_event":{"id":"c5c08b49-88d3-54e9-8a0a-e2b9a19912ea","stable_key":"31b1baa4-4113-5541-b9e7-fe44a5253a07:chorismate-l-tyrosine-event","event_type":"biochemical_relationship","label":"Chorismate supplies a multistep E. coli biosynthetic branch toward l-tyrosine.","description":"**Aromatic amino acids and competing branches.** Chorismate feeds organism-dependent synthesis of phenylalanine, tyrosine and tryptophan. 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[Metabolic engineering of Escherichia coli for shikimate pathway derivative production from glucose-xylose co-substrate.](https://pubmed.ncbi.nlm.nih.gov/31937786/)","status":"provisional","compartment":null,"participants":[{"entity":{"id":"849c016e-9dc8-567c-81b5-c8434c558a5f","slug":"chorismate","display_name":"Chorismate","entity_type_key":"small_molecule"},"role":"tested factor","stoichiometry":null,"state_label":"as reported","sequence_order":0,"notes":""},{"entity":{"id":"bcfef85f-831d-5439-ba51-1aef4b090441","slug":"l-tyrosine","display_name":"L-Tyrosine","entity_type_key":"small_molecule"},"role":"measured outcome","stoichiometry":null,"state_label":"not_reported","sequence_order":1,"notes":""}]},"contexts":[{"dimension":"evidence_access","value_text":"Primary full text retrieved; relevant methods/results/figures reviewed. 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[Metabolic engineering of Escherichia coli for shikimate pathway derivative production from glucose-xylose co-substrate.](https://pubmed.ncbi.nlm.nih.gov/31937786/)","model_system":"E. coli pathway map/engineering context.","directness":"reported_statement","verification_status":"source_derived_draft","notes":"Exact excerpt of the retained AI-assisted reviewed reference; primary sources are cited in primary_references and access scope is retained. Not a verbatim quotation from a primary paper.","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"e6ae59de-0369-5c2f-8262-57d91302671c","stable_key":"import-31b1baa4-4113-5541-b9e7-fe44a5253a07","title":"Shikimic acid: detailed mechanisms of action (reviewed 5 October 2026)","document_type":"imported_text","citation_label":"Original AI-assisted review of primary studies and, where relevant, official regulatory records. Access level is retained per claim. Corrections, null results and unresolved questions remain explicit. 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