{"id":"6a926c2d-df49-54e2-97fa-4b8dbb0bc235","stable_key":"44737fa3-b335-53f4-a644-b9878d4416ac:creatine-gamt-methyl-transfer","predicate":"methylates","statement":"GAMT transfers a methyl group from S-adenosylmethionine to guanidinoacetate, producing creatine and S-adenosylhomocysteine.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"cf6c2cb8-5c58-5c20-b5ec-eeb8b46a032f","mechanism_event_label":"The second synthesis step spends one SAM methyl group to finish each creatine molecule.","subject":{"id":"8530c377-5d52-52e8-b5ec-410f9e30e542","slug":"rat-gamt","display_name":"Rat guanidinoacetate methyltransferase / Gamt","entity_type_key":"protein"},"object":{"id":"84053a83-8fcc-5068-8df9-58f7e97fad76","slug":"guanidinoacetate","display_name":"Guanidinoacetate","entity_type_key":"small_molecule"},"evidence_count":1,"mechanism_event":{"id":"cf6c2cb8-5c58-5c20-b5ec-eeb8b46a032f","stable_key":"44737fa3-b335-53f4-a644-b9878d4416ac:creatine-gamt-methyl-transfer-event","event_type":"biochemical_relationship","label":"The second synthesis step spends one SAM methyl group to finish each creatine molecule.","description":"GAMT transfers a methyl group from S-adenosylmethionine to guanidinoacetate, producing creatine and S-adenosylhomocysteine.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"825f2da2-01bc-5874-a3c6-64f5ac867db5","slug":"s-adenosylmethionine","display_name":"S-Adenosyl-L-methionine","entity_type_key":"small_molecule"},"role":"methyl_donor","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"e84829b1-0607-558e-8add-aaa3af4747e7","slug":"s-adenosylhomocysteine","display_name":"S-Adenosyl-L-homocysteine","entity_type_key":"small_molecule"},"role":"product","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"9f5df558-ed3d-5cda-b5ca-0f90f7aa6a8c","slug":"creatine","display_name":"Creatine","entity_type_key":"small_molecule"},"role":"product","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"8530c377-5d52-52e8-b5ec-410f9e30e542","slug":"rat-gamt","display_name":"Rat guanidinoacetate methyltransferase / Gamt","entity_type_key":"protein"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""},{"entity":{"id":"84053a83-8fcc-5068-8df9-58f7e97fad76","slug":"guanidinoacetate","display_name":"Guanidinoacetate","entity_type_key":"small_molecule"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":4,"notes":""}]},"contexts":[{"dimension":"evidence_span","value_text":"{\"source_cache\": \"artifacts/creatine-research/12079381.abstract.txt\", \"locator\": \"Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"4f63981cbaa4b7614a24f0a637893d05f9eff2c2143991404b0a7af1ea6667c6\", \"start_char\": 0, \"end_char\": 1161, \"text_sha256\": \"4f63981cbaa4b7614a24f0a637893d05f9eff2c2143991404b0a7af1ea6667c6\"}","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"SAH-bound crystal structure and mutagenesis","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"SAH-bound structure at 2.5 angstrom resolution","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"The crystallized construct lacks 36 N-terminal residues; its dimer arrangement is not assigned universally to native human GAMT.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Creatine research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"creatine","display_name":"Creatine","entity_type_key":"small_molecule"}},{"dimension":"organism","value_text":"Rat GAMT","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"The second synthesis step spends one SAM methyl group to finish each creatine molecule.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[creatine-p12079381] Crystal structure of guanidinoacetate methyltransferase from rat liver: a model structure of protein arginine methyltransferase. (2002). https://pubmed.ncbi.nlm.nih.gov/12079381/ DOI: 10.1016/s0022-2836(02)00448-5\n[creatine-p11595668] Methylation demand and homocysteine metabolism: effects of dietary provision of creatine and guanidinoacetate. (2001). https://pubmed.ncbi.nlm.nih.gov/11595668/ DOI: 10.1152/ajpendo.2001.281.5.e1095","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Purified, N-terminally truncated enzyme","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"296b4973-1075-509e-9944-2279abe1cafa","evidence_kind":"source_excerpt","locator":"Lines 203-215","start_line":203,"end_line":215,"excerpt":"### creatine-gamt-methyl-transfer\nGAMT transfers a methyl group from S-adenosylmethionine to guanidinoacetate, producing creatine and S-adenosylhomocysteine.\nCondition category: normal\nnutrient_topic: Creatine research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: The second synthesis step spends one SAM methyl group to finish each creatine molecule.\norganism: Rat GAMT\ntissue_or_cell_type: Purified, N-terminally truncated enzyme\nexperimental_model: SAH-bound crystal structure and mutagenesis\nlimitations: The crystallized construct lacks 36 N-terminal residues; its dimer arrangement is not assigned universally to native human GAMT.\nexposure: SAH-bound structure at 2.5 angstrom resolution\nevidence_span: {\"source_cache\": \"artifacts/creatine-research/12079381.abstract.txt\", \"locator\": \"Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"4f63981cbaa4b7614a24f0a637893d05f9eff2c2143991404b0a7af1ea6667c6\", \"start_char\": 0, \"end_char\": 1161, \"text_sha256\": \"4f63981cbaa4b7614a24f0a637893d05f9eff2c2143991404b0a7af1ea6667c6\"}\n[creatine-p12079381] Crystal structure of guanidinoacetate methyltransferase from rat liver: a model structure of protein arginine methyltransferase. (2002). https://pubmed.ncbi.nlm.nih.gov/12079381/ DOI: 10.1016/s0022-2836(02)00448-5\n[creatine-p11595668] Methylation demand and homocysteine metabolism: effects of dietary provision of creatine and guanidinoacetate. (2001). https://pubmed.ncbi.nlm.nih.gov/11595668/ DOI: 10.1152/ajpendo.2001.281.5.e1095","model_system":"SAH-bound crystal structure and mutagenesis","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [creatine-p12079381] Crystal structure of guanidinoacetate methyltransferase from rat liver: a model structure of protein arginine methyltransferase. (2002). https://pubmed.ncbi.nlm.nih.gov/12079381/ DOI: 10.1016/s0022-2836(02)00448-5; [creatine-p11595668] Methylation demand and homocysteine metabolism: effects of dietary provision of creatine and guanidinoacetate. (2001). https://pubmed.ncbi.nlm.nih.gov/11595668/ DOI: 10.1152/ajpendo.2001.281.5.e1095","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"70358046-c5c3-5e9a-9fc9-eb01c3fff88b","stable_key":"import-44737fa3-b335-53f4-a644-b9878d4416ac","title":"Creatine: synthesis, transport, phosphocreatine energetics and nutrient interactions (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":"548237d3e98a73a7dc02181807921fdd8b902adcee46248792258a761593eda9","revision_id":"88738255-8028-52fb-9c12-0fe92d8ce367","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}