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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":"Making the methyl donor SAM is coupled to ATP-derived phosphate chemistry.","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":"6a05e350-0559-595d-b309-4fb615b9a3b1","evidence_kind":"source_excerpt","locator":"Lines 633-644","start_line":633,"end_line":644,"excerpt":"### phosphorus-mat-sam\nHuman MAT2A formed S-adenosylmethionine before rapid triphosphate hydrolysis and product release in the kinetic study.\nCondition category: normal\nnutrient_topic: Phosphorus research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Making the methyl donor SAM is coupled to ATP-derived phosphate chemistry.\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. Study references: [phosphorus-p33656855] Mechanism and Inhibition of Human Methionine Adenosyltransferase 2A. (2021). https://pubmed.ncbi.nlm.nih.gov/33656855/ DOI: 10.1021/acs.biochem.0c00998","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"cfdefe70-3a09-5e2e-97c8-46626382e4b4","stable_key":"import-fe6af7fc-7372-5c4f-9c2f-2bbf56695397","title":"Phosphorus: metabolism, signaling and nutrient connections (2026-09-17)","document_type":"imported_text","citation_label":"AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text.","file_path":"","sha256":"a04956d7177582b749608db404e6b691ae3b28a9f2f762781b6d820b461044fb","revision_id":"713b78f5-1133-5b2b-8822-20c0852e3715","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}