{"id":"e0a423c1-a2d1-5f55-b5fc-f2a0aebfbb18","stable_key":"31b1baa4-4113-5541-b9e7-fe44a5253a07:cp4-potassium","predicate":"increases_in_recorded_experiment","statement":"Potassium activated purified CP4 EPSPS, with a reported binding estimate around 25 mM.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"positive","is_public":true,"mechanism_event_id":"e2ae63ea-1647-5f4a-8b1b-81d973268822","mechanism_event_label":"Potassium activated purified CP4 EPSPS, with a reported binding estimate around 25 mM.","subject":{"id":"5dd31e52-f51e-51f3-880e-240abcc0ab1d","slug":"potassium-ion","display_name":"Potassium ion","entity_type_key":"ion"},"object":{"id":"4a4f865c-6706-50cc-bd79-cb07f3fa730b","slug":"cp4-epsps","display_name":"Agrobacterium strain CP4 EPSP synthase","entity_type_key":"protein"},"evidence_count":1,"mechanism_event":{"id":"e2ae63ea-1647-5f4a-8b1b-81d973268822","stable_key":"31b1baa4-4113-5541-b9e7-fe44a5253a07:cp4-potassium-event","event_type":"biochemical_relationship","label":"Potassium activated purified CP4 EPSPS, with a reported binding estimate around 25 mM.","description":"**Potassium dependence is enzyme-specific.** The CP4 EPSPS study found activation by K+, NH4+ and Rb+; the reported K+ dissociation estimate was approximately 25 mM. This result belongs to that purified bacterial enzyme. It does not mean human potassium intake controls all EPSPS enzymes or makes glyphosate inhibition irrelevant. [Molecular basis for the herbicide resistance of Roundup Ready crops.](https://pubmed.ncbi.nlm.nih.gov/16916934/)","status":"provisional","compartment":null,"participants":[{"entity":{"id":"5dd31e52-f51e-51f3-880e-240abcc0ab1d","slug":"potassium-ion","display_name":"Potassium ion","entity_type_key":"ion"},"role":"tested factor","stoichiometry":null,"state_label":"K+ supplied in enzyme assay","sequence_order":0,"notes":""},{"entity":{"id":"4a4f865c-6706-50cc-bd79-cb07f3fa730b","slug":"cp4-epsps","display_name":"Agrobacterium strain CP4 EPSP synthase","entity_type_key":"protein"},"role":"measured outcome","stoichiometry":null,"state_label":"increase","sequence_order":1,"notes":""}]},"contexts":[{"dimension":"evidence_access","value_text":"Primary full-text HTML and indexed abstract reviewed for the stated results; archived locally.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_contrast","value_text":"{\"intervention\": \"K+ supplied in enzyme assay\", \"comparator\": \"Assay without activating monovalent cation\", \"endpoint\": \"Potassium activated purified CP4 EPSPS, with a reported binding estimate around 25 mM.\", \"effect_direction\": \"increase\", \"combination\": \"single\", \"conditions\": []}","comparator":null,"unit":null,"notes":"Explicit extracted experimental comparison; source-derived draft.","entity":null},{"dimension":"experimental_model","value_text":"Purified strain CP4 enzyme; monovalent-cation comparison.","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":"Specific bacterial enzyme, not human potassium status or a universal EPSPS gate.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"Potassium activated purified CP4 EPSPS, with a reported binding estimate around 25 mM.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"Molecular basis for the herbicide resistance of Roundup Ready crops. | 2006 | DOI 10.1073/pnas.0603638103 | PMID 16916934 | https://pubmed.ncbi.nlm.nih.gov/16916934/ | https://doi.org/10.1073/pnas.0603638103 | https://pmc.ncbi.nlm.nih.gov/articles/PMC1559744/","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"source_locator","value_text":"Reviewed reference lines 19-19; exact primary location described in quoted passage where extracted.","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"a04f30cb-850a-5aa3-a95e-0667737ec42f","evidence_kind":"source_excerpt","locator":"Lines 19-19","start_line":19,"end_line":19,"excerpt":"**Potassium dependence is enzyme-specific.** The CP4 EPSPS study found activation by K+, NH4+ and Rb+; the reported K+ dissociation estimate was approximately 25 mM. This result belongs to that purified bacterial enzyme. It does not mean human potassium intake controls all EPSPS enzymes or makes glyphosate inhibition irrelevant. [Molecular basis for the herbicide resistance of Roundup Ready crops.](https://pubmed.ncbi.nlm.nih.gov/16916934/)","model_system":"Purified strain CP4 enzyme; monovalent-cation comparison.","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. 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