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it does not identify every species in living cells.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Vanadium collection; molecular form, preparation, species, exposure and manipulation remain explicit.","comparator":null,"unit":null,"notes":"","entity":{"slug":"vanadium","display_name":"Vanadium","entity_type_key":"nutrient_element"}},{"dimension":"plain_language","value_text":"An assay can generate a second inhibitor while it runs.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"Mechanism of inhibition of protein-tyrosine phosphatases by vanadate and pervanadate. · 1997 · https://pubmed.ncbi.nlm.nih.gov/8995372/ · DOI 10.1074/jbc.272.2.843","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"c4862227-e517-5f44-9195-41abf934e2e9","evidence_kind":"source_excerpt","locator":"Lines 46-52","start_line":46,"end_line":52,"excerpt":"## vanadium-catalase-artifact\nAn assay can generate a second inhibitor while it runs.\nCatalase blocked the slow time-dependent inactivation seen under some vanadate conditions, supporting an in-situ peroxide/pervanadate contribution.\nModel: PTP1B time-course experiments with catalase.\nLimitations: Catalase rescue supports peroxide involvement; it does not identify every species in living cells.\nEvidence access: Primary abstract\nMechanism of inhibition of protein-tyrosine phosphatases by vanadate and pervanadate. · 1997 · https://pubmed.ncbi.nlm.nih.gov/8995372/ · DOI 10.1074/jbc.272.2.843","model_system":"PTP1B time-course experiments with catalase.","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":"e4d5d0ba-529b-540f-96ed-e719d116ccfd","stable_key":"import-335be270-ea4a-5c8e-ad04-964fd22a439e","title":"Vanadium: speciation, phosphate-sensitive enzymes 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. 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