{"id":"257ad5e6-bb80-5d5c-a6eb-9d701d84ee46","stable_key":"7fc92b9e-9cbf-556e-8719-6b5244625250:mmaa-hydrolyzes-gtp","predicate":"hydrolyzes","statement":"Purified human MMAA displayed intrinsic GTPase activity modulated by human MMUT.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"positive","is_public":true,"mechanism_event_id":"306dd1ed-7278-5109-a37f-854faac50716","mechanism_event_label":"Human MMAA consumed GTP in the protein assay, linking energy use to B12 handling.","subject":{"id":"39366dce-a30d-5e74-8c86-2bd8ca0bad96","slug":"mmaa","display_name":"Human MMAA GTPase","entity_type_key":"protein"},"object":{"id":"c8ccc03a-29cc-5127-baf5-81eeb92ac780","slug":"gtp","display_name":"Guanosine triphosphate","entity_type_key":"small_molecule"},"evidence_count":1,"mechanism_event":{"id":"306dd1ed-7278-5109-a37f-854faac50716","stable_key":"7fc92b9e-9cbf-556e-8719-6b5244625250:mmaa-hydrolyzes-gtp-event","event_type":"biochemical_relationship","label":"Human MMAA consumed GTP in the protein assay, linking energy use to B12 handling.","description":"Purified human MMAA displayed intrinsic GTPase activity modulated by human MMUT.","status":"provisional","compartment":{"slug":"mitochondrial-matrix","display_name":"Mitochondrial matrix"},"participants":[{"entity":{"id":"f30bc32c-5319-5d92-a856-135b64d4d043","slug":"gdp","display_name":"Guanosine diphosphate","entity_type_key":"small_molecule"},"role":"product","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"8f690797-c976-5a5e-886e-dc49d1b17f5a","slug":"mmut","display_name":"Human methylmalonyl-CoA mutase / MMUT","entity_type_key":"protein"},"role":"modulator","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"39366dce-a30d-5e74-8c86-2bd8ca0bad96","slug":"mmaa","display_name":"Human MMAA GTPase","entity_type_key":"protein"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"c8ccc03a-29cc-5127-baf5-81eeb92ac780","slug":"gtp","display_name":"Guanosine triphosphate","entity_type_key":"small_molecule"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""}]},"contexts":[{"dimension":"cross_nutrient","value_text":"false","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"evidence_location","value_text":"Indexed primary abstract; indexed Results","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Purified human proteins","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"GTP hydrolysis assay","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Biochemical reconstitution; does not determine cellular rate or dietary requirement.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Vitamin B12 research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"vitamin-b12","display_name":"Vitamin B12 (cobalamins)","entity_type_key":"chemical_species"}},{"dimension":"organism","value_text":"Homo sapiens","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"Human MMAA consumed GTP in the protein assay, linking energy use to B12 handling.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[froese-2010-human-mmaa] Structures of the human GTPase MMAA and vitamin B12-dependent methylmalonyl-CoA mutase and insight into their complex formation. (2010). https://pubmed.ncbi.nlm.nih.gov/20876572/ DOI: 10.1074/jbc.m110.177717","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Purified protein assay","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"0ad6451e-4f5a-5216-9993-1c38b0523280","evidence_kind":"source_excerpt","locator":"Lines 1033-1045","start_line":1033,"end_line":1045,"excerpt":"### mmaa-hydrolyzes-gtp\nPurified human MMAA displayed intrinsic GTPase activity modulated by human MMUT.\nCondition category: normal\nnutrient_topic: Vitamin B12 research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Human MMAA consumed GTP in the protein assay, linking energy use to B12 handling.\norganism: Homo sapiens\ntissue_or_cell_type: Purified protein assay\nexperimental_model: Purified human proteins\nlimitations: Biochemical reconstitution; does not determine cellular rate or dietary requirement.\nexposure: GTP hydrolysis assay\ncross_nutrient: false\nevidence_location: Indexed primary abstract; indexed Results\n[froese-2010-human-mmaa] Structures of the human GTPase MMAA and vitamin B12-dependent methylmalonyl-CoA mutase and insight into their complex formation. 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