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Metal contacts were resolved with an experimental ATP-site ligand.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Phosphorus research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"phosphorus","display_name":"Phosphorus","entity_type_key":"nutrient_element"}},{"dimension":"organism","value_text":"Human recombinant enzyme","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"Potassium and magnesium had distinct contacts in the same phosphate-handling active site.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[phosphorus-p33656855] Mechanism and Inhibition of Human Methionine Adenosyltransferase 2A. (2021). https://pubmed.ncbi.nlm.nih.gov/33656855/ DOI: 10.1021/acs.biochem.0c00998","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Purified MAT2A active site","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"d3194744-8f3a-5617-8d01-ff0b5682a5bf","evidence_kind":"source_excerpt","locator":"Lines 672-683","start_line":672,"end_line":683,"excerpt":"### phosphorus-mat-potassium\nThe beta-phosphoryl oxygen of the MAT2A-bound PNPNP ligand contacted the essential potassium ion.\nCondition category: normal\nnutrient_topic: Phosphorus research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Potassium and magnesium had distinct contacts in the same phosphate-handling active site.\norganism: Human recombinant enzyme\ntissue_or_cell_type: Purified MAT2A active site\nexperimental_model: Human MAT2A kinetics, isotope exchange and inhibitor-bound crystallography\nlimitations: Phosphoryl chemistry is not evidence that phosphate supplements boost methylation. Metal contacts were resolved with an experimental ATP-site ligand.\nexposure: ATP/methionine reactions and PNPNP ligand complexes\nevidence_span: {\"source_cache\": \"artifacts/phosphorus-research/33656855.abstract.txt\", \"locator\": \"Primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"1d45073f7187a06cfb9b2d630f94fa651239f0a9a5ae353b37d9af90750f2f38\", \"start_char\": 0, \"end_char\": 1520, \"text_sha256\": \"1d45073f7187a06cfb9b2d630f94fa651239f0a9a5ae353b37d9af90750f2f38\"}\n[phosphorus-p33656855] Mechanism and Inhibition of Human Methionine Adenosyltransferase 2A. (2021). https://pubmed.ncbi.nlm.nih.gov/33656855/ DOI: 10.1021/acs.biochem.0c00998","model_system":"Human MAT2A kinetics, isotope exchange and inhibitor-bound crystallography","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. 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