{"id":"9368457c-59ea-5a4b-b793-71a0e702a672","stable_key":"31b1baa4-4113-5541-b9e7-fe44a5253a07:kinase-double-loss","predicate":"increases_in_recorded_experiment","statement":"Loss of both AroK and AroL produces aromatic-amino-acid auxotrophy in E. coli.","claim_class":"observational","status":"source_recorded","evidence_grade":"ungraded","direction":"positive","is_public":true,"mechanism_event_id":"504641e8-8ce3-5d16-9f91-3a4427c451a8","mechanism_event_label":"Loss of both AroK and AroL produces aromatic-amino-acid auxotrophy in E. coli.","subject":{"id":"71659bcc-4aaf-57af-a4df-e8affd61b300","slug":"ecoli-arok","display_name":"Escherichia coli shikimate kinase I / AroK","entity_type_key":"protein"},"object":{"id":"75347370-8c44-585e-8c50-b4e49a4346eb","slug":"ecoli-aromatic-amino-acid-auxotrophy","display_name":"E. coli growth dependent on external aromatic amino acids","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"504641e8-8ce3-5d16-9f91-3a4427c451a8","stable_key":"31b1baa4-4113-5541-b9e7-fe44a5253a07:kinase-double-loss-event","event_type":"experimental_observation","label":"Loss of both AroK and AroL produces aromatic-amino-acid auxotrophy in E. coli.","description":"**ATP and magnesium at shikimate kinase.** Shikimate kinase transfers a phosphoryl group from ATP to shikimate, yielding shikimate-3-phosphate and ADP. 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[Biochemical and X-ray crystallographic studies on shikimate kinase: the important structural role of the P-loop lysine.](https://pubmed.ncbi.nlm.nih.gov/11369852/) [Crystal structure of the Escherichia coli shikimate kinase I (AroK) that confers sensitivity to mecillinam.](https://pubmed.ncbi.nlm.nih.gov/12001235/)","status":"provisional","compartment":null,"participants":[{"entity":{"id":"71659bcc-4aaf-57af-a4df-e8affd61b300","slug":"ecoli-arok","display_name":"Escherichia coli shikimate kinase I / AroK","entity_type_key":"protein"},"role":"tested factor","stoichiometry":null,"state_label":"Both AroK and AroL unavailable","sequence_order":0,"notes":""},{"entity":{"id":"75347370-8c44-585e-8c50-b4e49a4346eb","slug":"ecoli-aromatic-amino-acid-auxotrophy","display_name":"E. coli growth dependent on external aromatic amino acids","entity_type_key":"cellular_process"},"role":"measured outcome","stoichiometry":null,"state_label":"increase","sequence_order":1,"notes":""},{"entity":{"id":"f06494fa-75b1-5e55-a0dd-7dd9642a1ffb","slug":"ecoli-arol","display_name":"Escherichia coli shikimate kinase II / AroL","entity_type_key":"protein"},"role":"jointly lost isoenzyme","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"190407ad-0219-54b5-b05f-7c75f3895ca6","slug":"l-phenylalanine","display_name":"L-Phenylalanine","entity_type_key":"small_molecule"},"role":"external rescue nutrient class","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""},{"entity":{"id":"bcfef85f-831d-5439-ba51-1aef4b090441","slug":"l-tyrosine","display_name":"L-Tyrosine","entity_type_key":"small_molecule"},"role":"external rescue nutrient class","stoichiometry":null,"state_label":"","sequence_order":4,"notes":""},{"entity":{"id":"769339cb-213b-559e-acc0-07ed00368b94","slug":"l-tryptophan","display_name":"L-Tryptophan","entity_type_key":"small_molecule"},"role":"external rescue nutrient class","stoichiometry":null,"state_label":"","sequence_order":5,"notes":""}]},"contexts":[{"dimension":"availability_state","value_text":"machinery_impairment","comparator":null,"unit":null,"notes":"Imported condition classification; unverified.","entity":null},{"dimension":"evidence_access","value_text":"Primary full-text HTML and indexed abstract reviewed for the stated results; archived locally.\nPrimary publisher article introductory text reviewed; precise affinity estimates are contextual, not newly remeasured.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_condition","value_text":"lost","comparator":"Functional shikimate kinase background","unit":null,"notes":"Condition belongs to the full experimental contrast; do not separate a joint intervention.","entity":{"slug":"ecoli-arok","display_name":"Escherichia coli shikimate kinase I / AroK","entity_type_key":"protein"}},{"dimension":"experimental_condition","value_text":"lost","comparator":"Functional shikimate kinase background","unit":null,"notes":"Condition belongs to the full experimental contrast; do not separate a joint intervention.","entity":{"slug":"ecoli-arol","display_name":"Escherichia coli shikimate kinase II / AroL","entity_type_key":"protein"}},{"dimension":"experimental_contrast","value_text":"{\"intervention\": \"Both AroK and AroL unavailable\", \"comparator\": \"Functional shikimate kinase background\", \"endpoint\": \"Loss of both AroK and AroL produces aromatic-amino-acid auxotrophy in E. coli.\", \"effect_direction\": \"increase\", \"combination\": \"joint\", \"conditions\": [{\"entity_slug\": \"ecoli-arok\", \"state\": \"lost\"}, {\"entity_slug\": \"ecoli-arol\", \"state\": \"lost\"}]}","comparator":null,"unit":null,"notes":"Explicit extracted experimental comparison; source-derived draft.","entity":null},{"dimension":"experimental_model","value_text":"E. coli double-kinase loss phenotype discussed in the primary structural study.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"interpretation_status","value_text":"Source-derived extraction of a fact-checked reference; access is explicit, not independent raw-data verification.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Interpret only within the recorded preparation, exposure and comparator. 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[Biochemical and X-ray crystallographic studies on shikimate kinase: the important structural role of the P-loop lysine.](https://pubmed.ncbi.nlm.nih.gov/11369852/) [Crystal structure of the Escherichia coli shikimate kinase I (AroK) that confers sensitivity to mecillinam.](https://pubmed.ncbi.nlm.nih.gov/12001235/)","model_system":"E. coli double-kinase loss phenotype discussed in the primary structural study.","directness":"reported_statement","verification_status":"source_recorded","notes":"Exact excerpt of the retained AI-assisted reviewed reference; primary sources are cited in primary_references and access scope is retained. 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