{"id":"6a83a3e5-88ef-5db3-ac79-d28662db0b07","stable_key":"7fc92b9e-9cbf-556e-8719-6b5244625250:b12-cblc-propyl-probe","predicate":"pathogenic-variants-impair-processing-of","statement":"Fibroblasts from three cblC patients had little or no conversion of cobalt-57-labeled propylcobalamin into adenosylcobalamin and methylcobalamin, whereas control skin fibroblasts converted the probe.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"negative","is_public":true,"mechanism_event_id":"d2c0469b-d1ba-5e85-a49a-33630c4be165","mechanism_event_label":"A synthetic B12 probe exposed the processing defect in patient cells.","subject":{"id":"72124e1e-7779-5875-92b9-85aee38ecf94","slug":"mmachc-human-gene","display_name":"Human MMACHC gene","entity_type_key":"gene"},"object":{"id":"48ef65f0-53d7-5a09-9922-ba82834a2bd9","slug":"propylcobalamin","display_name":"Propylcobalamin","entity_type_key":"small_molecule"},"evidence_count":1,"mechanism_event":{"id":"d2c0469b-d1ba-5e85-a49a-33630c4be165","stable_key":"7fc92b9e-9cbf-556e-8719-6b5244625250:b12-cblc-propyl-probe-event","event_type":"biochemical_relationship","label":"A synthetic B12 probe exposed the processing defect in patient cells.","description":"Fibroblasts from three cblC patients had little or no conversion of cobalt-57-labeled propylcobalamin into adenosylcobalamin and methylcobalamin, whereas control skin fibroblasts converted the probe.","status":"provisional","compartment":{"slug":"cytosol","display_name":"Cytosol"},"participants":[{"entity":{"id":"07657685-74aa-5d99-8625-0f6a3b521f07","slug":"adenosylcobalamin","display_name":"5'-Deoxyadenosylcobalamin","entity_type_key":"small_molecule"},"role":"measured product","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"6563fbad-ebdc-5408-966a-d24f8b8cd854","slug":"methylcobalamin","display_name":"Methylcobalamin","entity_type_key":"small_molecule"},"role":"measured product","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"72124e1e-7779-5875-92b9-85aee38ecf94","slug":"mmachc-human-gene","display_name":"Human MMACHC gene","entity_type_key":"gene"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"48ef65f0-53d7-5a09-9922-ba82834a2bd9","slug":"propylcobalamin","display_name":"Propylcobalamin","entity_type_key":"small_molecule"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""}]},"contexts":[{"dimension":"availability_state","value_text":"machinery_impairment","comparator":null,"unit":null,"notes":"Imported condition classification; 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indexed Methods: Assessment of dealkylation; Discussion\n[hannibal-2009-cell-processing] Processing of alkylcobalamins in mammalian cells: A role for the MMACHC (cblC) gene product (2009). https://pubmed.ncbi.nlm.nih.gov/19447654/ DOI: 10.1016/j.ymgme.2009.04.005","model_system":"Human control and cblC patient fibroblast labeling","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [hannibal-2009-cell-processing] Processing of alkylcobalamins in mammalian cells: A role for the MMACHC (cblC) gene product (2009). https://pubmed.ncbi.nlm.nih.gov/19447654/ DOI: 10.1016/j.ymgme.2009.04.005","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}