{"id":"f9856d82-0f21-5705-800a-eb3df6933a51","stable_key":"fe6af7fc-7372-5c4f-9c2f-2bbf56695397:phosphorus-mat-pi","predicate":"is_hydrolyzed_to","statement":"After SAM formation, MAT2A rapidly hydrolyzed the beta–gamma bond of triphosphate and released phosphate and pyrophosphate.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"d83662af-299f-5ff0-b713-22ea3f8a4260","mechanism_event_label":"ATP’s phosphate chain is processed into two separately tracked products.","subject":{"id":"7ac4f26c-bc7d-57bc-9910-43164518289f","slug":"triphosphate","display_name":"Inorganic triphosphate","entity_type_key":"small_molecule"},"object":{"id":"ee63fe8e-92f3-552f-8049-a5f1fa1e1523","slug":"phosphate-ion","display_name":"Inorganic phosphate (Pi; protonation depends on pH)","entity_type_key":"ion"},"evidence_count":1,"mechanism_event":{"id":"d83662af-299f-5ff0-b713-22ea3f8a4260","stable_key":"fe6af7fc-7372-5c4f-9c2f-2bbf56695397:phosphorus-mat-pi-event","event_type":"biochemical_relationship","label":"ATP’s phosphate chain is processed into two separately tracked products.","description":"After SAM formation, MAT2A rapidly hydrolyzed the beta–gamma bond of triphosphate and released phosphate and pyrophosphate.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"bbc04455-e242-5f4d-9a6c-5b2ee6a6cb41","slug":"human-mat2a","display_name":"Human methionine adenosyltransferase 2A / MAT2A","entity_type_key":"protein"},"role":"enzyme","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"cd026fef-529f-5e03-b6b5-37ede8ce9127","slug":"pyrophosphate","display_name":"Inorganic pyrophosphate","entity_type_key":"small_molecule"},"role":"coproduct","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"7ac4f26c-bc7d-57bc-9910-43164518289f","slug":"triphosphate","display_name":"Inorganic triphosphate","entity_type_key":"small_molecule"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"ee63fe8e-92f3-552f-8049-a5f1fa1e1523","slug":"phosphate-ion","display_name":"Inorganic phosphate (Pi; protonation depends on pH)","entity_type_key":"ion"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""}]},"contexts":[{"dimension":"evidence_span","value_text":"{\"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\"}","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Human MAT2A kinetics, isotope exchange and inhibitor-bound crystallography","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"ATP/methionine reactions and PNPNP ligand complexes","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Phosphoryl chemistry is not evidence that phosphate supplements boost methylation. 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":"ATP’s phosphate chain is processed into two separately tracked products.","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":"cb6df603-3ebb-5a0b-ba67-bee13dc5971f","evidence_kind":"source_excerpt","locator":"Lines 646-657","start_line":646,"end_line":657,"excerpt":"### phosphorus-mat-pi\nAfter SAM formation, MAT2A rapidly hydrolyzed the beta–gamma bond of triphosphate and released phosphate and pyrophosphate.\nCondition category: normal\nnutrient_topic: Phosphorus research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: ATP’s phosphate chain is processed into two separately tracked products.\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}