{"id":"c86f07a4-2e36-5ee0-9d51-9b7af190a855","stable_key":"44737fa3-b335-53f4-a644-b9878d4416ac:creatine-ornithine-agat","predicate":"binds_product_inhibitor_site_of","statement":"Ornithine binding to human AGAT induced movement of a flexible loop and neighboring helix at the active-site region.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"fecfaa82-65f8-5522-a4d0-686bb544ec24","mechanism_event_label":"A product of the first step can bind back to the enzyme and change its working shape.","subject":{"id":"c715e48e-42db-5fac-b4a4-c1285a68d085","slug":"ornithine","display_name":"L-Ornithine","entity_type_key":"small_molecule"},"object":{"id":"c8ab5c45-4253-5dd5-be9c-2fcdfa69ac3a","slug":"gatm","display_name":"Human glycine amidinotransferase AGAT / GATM","entity_type_key":"protein"},"evidence_count":1,"mechanism_event":{"id":"fecfaa82-65f8-5522-a4d0-686bb544ec24","stable_key":"44737fa3-b335-53f4-a644-b9878d4416ac:creatine-ornithine-agat-event","event_type":"biochemical_relationship","label":"A product of the first step can bind back to the enzyme and change its working shape.","description":"Ornithine binding to human AGAT induced movement of a flexible loop and neighboring helix at the active-site region.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"c715e48e-42db-5fac-b4a4-c1285a68d085","slug":"ornithine","display_name":"L-Ornithine","entity_type_key":"small_molecule"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"c8ab5c45-4253-5dd5-be9c-2fcdfa69ac3a","slug":"gatm","display_name":"Human glycine amidinotransferase AGAT / GATM","entity_type_key":"protein"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""}]},"contexts":[{"dimension":"evidence_span","value_text":"{\"source_cache\": \"artifacts/creatine-research/9218780.abstract.txt\", \"locator\": \"Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"407baedc2f982a5abb9d14a01e8ac9dc331d60115acc716604c1e6003aa12c1b\", \"start_char\": 0, \"end_char\": 1112, \"text_sha256\": \"407baedc2f982a5abb9d14a01e8ac9dc331d60115acc716604c1e6003aa12c1b\"}","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Human AGAT crystal structures and inactive-mutant substrate complex","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"Native, ornithine-bound and inactive mutant structures","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Structures support an amidino-transfer mechanism; substrate availability in a person and effects of amino-acid supplementation were not measured.","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":"Recombinant human enzyme","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"A product of the first step can bind back to the enzyme and change its working shape.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[creatine-p9218780] Crystal structure and mechanism of human L-arginine:glycine amidinotransferase: a mitochondrial enzyme involved in creatine biosynthesis. (1997). https://pubmed.ncbi.nlm.nih.gov/9218780/ DOI: 10.1093/emboj/16.12.3373","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Purified protein","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"6a2848eb-8e36-5c74-ba4d-09a98f24d48d","evidence_kind":"source_excerpt","locator":"Lines 190-201","start_line":190,"end_line":201,"excerpt":"### creatine-ornithine-agat\nOrnithine binding to human AGAT induced movement of a flexible loop and neighboring helix at the active-site region.\nCondition category: normal\nnutrient_topic: Creatine research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: A product of the first step can bind back to the enzyme and change its working shape.\norganism: Recombinant human enzyme\ntissue_or_cell_type: Purified protein\nexperimental_model: Human AGAT crystal structures and inactive-mutant substrate complex\nlimitations: Structures support an amidino-transfer mechanism; substrate availability in a person and effects of amino-acid supplementation were not measured.\nexposure: Native, ornithine-bound and inactive mutant structures\nevidence_span: {\"source_cache\": \"artifacts/creatine-research/9218780.abstract.txt\", \"locator\": \"Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"407baedc2f982a5abb9d14a01e8ac9dc331d60115acc716604c1e6003aa12c1b\", \"start_char\": 0, \"end_char\": 1112, \"text_sha256\": \"407baedc2f982a5abb9d14a01e8ac9dc331d60115acc716604c1e6003aa12c1b\"}\n[creatine-p9218780] Crystal structure and mechanism of human L-arginine:glycine amidinotransferase: a mitochondrial enzyme involved in creatine biosynthesis. (1997). https://pubmed.ncbi.nlm.nih.gov/9218780/ DOI: 10.1093/emboj/16.12.3373","model_system":"Human AGAT crystal structures and inactive-mutant substrate complex","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [creatine-p9218780] Crystal structure and mechanism of human L-arginine:glycine amidinotransferase: a mitochondrial enzyme involved in creatine biosynthesis. 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