{"id":"5b192a95-059e-5498-a945-d8e50528927d","stable_key":"7fc92b9e-9cbf-556e-8719-6b5244625250:mmaa-g188r-loses-mmut-interaction","predicate":"impairs-binding-to","statement":"Human MMAA G188R retained basal GTPase activity but lost the detected MMUT interaction.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"negative","is_public":true,"mechanism_event_id":"884e801b-3921-57c9-bbc0-e30eb951e641","mechanism_event_label":"In the human-protein experiment, this MMAA variant still hydrolyzed GTP but failed to bind MMUT normally.","subject":{"id":"375f0424-cedd-598e-a37c-88a7b4602991","slug":"mmaa-g188r","display_name":"Human MMAA p.Gly188Arg","entity_type_key":"protein_state"},"object":{"id":"8f690797-c976-5a5e-886e-dc49d1b17f5a","slug":"mmut","display_name":"Human methylmalonyl-CoA mutase / MMUT","entity_type_key":"protein"},"evidence_count":1,"mechanism_event":{"id":"884e801b-3921-57c9-bbc0-e30eb951e641","stable_key":"7fc92b9e-9cbf-556e-8719-6b5244625250:mmaa-g188r-loses-mmut-interaction-event","event_type":"biochemical_relationship","label":"In the human-protein experiment, this MMAA variant still hydrolyzed GTP but failed to bind MMUT normally.","description":"Human MMAA G188R retained basal GTPase activity but lost the detected MMUT interaction.","status":"provisional","compartment":{"slug":"mitochondrial-matrix","display_name":"Mitochondrial matrix"},"participants":[{"entity":{"id":"375f0424-cedd-598e-a37c-88a7b4602991","slug":"mmaa-g188r","display_name":"Human MMAA p.Gly188Arg","entity_type_key":"protein_state"},"role":"subject","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":"target","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""}]},"contexts":[{"dimension":"availability_state","value_text":"machinery_impairment","comparator":null,"unit":null,"notes":"Imported condition classification; unverified.","entity":null},{"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":"Human MMAA G188R functional assays","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"G188R patient variant versus wild type","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Interaction defect in experimental assays; residual tissue-specific function was not quantified.","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":"In the human-protein experiment, this MMAA variant still hydrolyzed GTP but failed to bind MMUT normally.","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},{"dimension":"trigger_kind","value_text":"machinery_impairment","comparator":null,"unit":null,"notes":"Imported condition classification; unverified.","entity":null}],"evidence":[{"id":"912955a4-2363-574a-b813-c6b495e1e328","evidence_kind":"source_excerpt","locator":"Lines 1061-1073","start_line":1061,"end_line":1073,"excerpt":"### mmaa-g188r-loses-mmut-interaction\nHuman MMAA G188R retained basal GTPase activity but lost the detected MMUT interaction.\nCondition category: machinery_impairment\nnutrient_topic: Vitamin B12 research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: In the human-protein experiment, this MMAA variant still hydrolyzed GTP but failed to bind MMUT normally.\norganism: Homo sapiens\ntissue_or_cell_type: Purified protein assay\nexperimental_model: Human MMAA G188R functional assays\nlimitations: Interaction defect in experimental assays; residual tissue-specific function was not quantified.\nexposure: G188R patient variant versus wild type\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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