{"id":"59b0c68e-6eef-5afc-8aa8-83f19712ae9f","stable_key":"7fc92b9e-9cbf-556e-8719-6b5244625250:mmut-isomerizes-r-methylmalonyl-coa","predicate":"isomerizes","statement":"Adenosylcobalamin-loaded human MMUT converts (R)-methylmalonyl-CoA to succinyl-CoA in the coupled enzyme assay.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"positive","is_public":true,"mechanism_event_id":"25a84c35-4a2b-555a-9c13-f01f7289d287","mechanism_event_label":"Purified human MMUT used activated B12 to make succinyl-CoA from the matching methylmalonyl-CoA epimer.","subject":{"id":"8f690797-c976-5a5e-886e-dc49d1b17f5a","slug":"mmut","display_name":"Human methylmalonyl-CoA mutase / MMUT","entity_type_key":"protein"},"object":{"id":"3a142dbd-fc69-58b9-bcc7-4fa1ffe14374","slug":"r-methylmalonyl-coa","display_name":"(R)-Methylmalonyl-CoA","entity_type_key":"small_molecule"},"evidence_count":1,"mechanism_event":{"id":"25a84c35-4a2b-555a-9c13-f01f7289d287","stable_key":"7fc92b9e-9cbf-556e-8719-6b5244625250:mmut-isomerizes-r-methylmalonyl-coa-event","event_type":"biochemical_relationship","label":"Purified human MMUT used activated B12 to make succinyl-CoA from the matching methylmalonyl-CoA epimer.","description":"Adenosylcobalamin-loaded human MMUT converts (R)-methylmalonyl-CoA to succinyl-CoA in the coupled enzyme assay.","status":"provisional","compartment":{"slug":"mitochondrial-matrix","display_name":"Mitochondrial matrix"},"participants":[{"entity":{"id":"07657685-74aa-5d99-8625-0f6a3b521f07","slug":"adenosylcobalamin","display_name":"5'-Deoxyadenosylcobalamin","entity_type_key":"small_molecule"},"role":"cofactor","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"1b7ace51-f2c3-583b-89ed-196fa96d2b0a","slug":"succinyl-coa","display_name":"Succinyl-CoA","entity_type_key":"small_molecule"},"role":"product","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"8f690797-c976-5a5e-886e-dc49d1b17f5a","slug":"mmut","display_name":"Human methylmalonyl-CoA mutase / MMUT","entity_type_key":"protein"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"3a142dbd-fc69-58b9-bcc7-4fa1ffe14374","slug":"r-methylmalonyl-coa","display_name":"(R)-Methylmalonyl-CoA","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":"Full text Results; Figures 2-4; cofactor off-loading and MMUT activity Methods","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":"AdoCbl-loaded MMUT and methylmalonyl-CoA; thiokinase-coupled readout","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Product formation is a coupled assay; cellular net flux was not measured.","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":"Purified human MMUT used activated B12 to make succinyl-CoA from the matching methylmalonyl-CoA epimer.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[mascarenhas-2023-nanoassembly] Architecture of the human G-protein-methylmalonyl-CoA mutase nanoassembly for B12 delivery and repair. (2023). https://pubmed.ncbi.nlm.nih.gov/37468522/ DOI: 10.1038/s41467-023-40077-4","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":"821f4991-359b-5b3b-990a-264dd548909e","evidence_kind":"source_excerpt","locator":"Lines 1103-1115","start_line":1103,"end_line":1115,"excerpt":"### mmut-isomerizes-r-methylmalonyl-coa\nAdenosylcobalamin-loaded human MMUT converts (R)-methylmalonyl-CoA to succinyl-CoA in the coupled enzyme assay.\nCondition category: normal\nnutrient_topic: Vitamin B12 research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Purified human MMUT used activated B12 to make succinyl-CoA from the matching methylmalonyl-CoA epimer.\norganism: Homo sapiens\ntissue_or_cell_type: Purified protein assay\nexperimental_model: Purified human proteins\nlimitations: Product formation is a coupled assay; cellular net flux was not measured.\nexposure: AdoCbl-loaded MMUT and methylmalonyl-CoA; thiokinase-coupled readout\ncross_nutrient: false\nevidence_location: Full text Results; Figures 2-4; cofactor off-loading and MMUT activity Methods\n[mascarenhas-2023-nanoassembly] Architecture of the human G-protein-methylmalonyl-CoA mutase nanoassembly for B12 delivery and repair. (2023). https://pubmed.ncbi.nlm.nih.gov/37468522/ DOI: 10.1038/s41467-023-40077-4","model_system":"Purified human proteins","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [mascarenhas-2023-nanoassembly] Architecture of the human G-protein-methylmalonyl-CoA mutase nanoassembly for B12 delivery and repair. (2023). https://pubmed.ncbi.nlm.nih.gov/37468522/ DOI: 10.1038/s41467-023-40077-4","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"73145023-2982-5848-aff2-8d8875d6b9c5","stable_key":"import-7fc92b9e-9cbf-556e-8719-6b5244625250","title":"Vitamin B12: mechanisms, deficiency 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":"ad5b3a51d36e856aa7fdfd1cc23f690b094689bad87d28e1a621a54675a01c92","revision_id":"118bd616-0c13-549f-bfeb-bc439715b89c","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}