{"id":"3d02d380-4977-54d6-abd9-4411da168a92","stable_key":"6cdb37aa-8998-5ea8-829d-4f995caf98fc:l-carnitine-tissue-synthesis","predicate":"converted_in","statement":"Human tissue assays detected gamma-butyrobetaine-to-carnitine activity in liver, kidney and brain, but not heart or skeletal muscle; the earlier steps were detected in all five tissues.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"2cad9e6c-913d-5394-9f5c-1df261c82458","mechanism_event_label":"Some tissues rely on importing the finished molecule.","subject":{"id":"e83c0395-55f1-5483-9710-9b9aa9767689","slug":"gamma-butyrobetaine","display_name":"gamma-Butyrobetaine","entity_type_key":"small_molecule"},"object":{"id":"7d5d7543-391b-50a3-96f8-5e3ca6943f3c","slug":"human-carnitine-biosynthesis-tissue-activity","display_name":"Human tissue carnitine biosynthetic enzyme activity","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"2cad9e6c-913d-5394-9f5c-1df261c82458","stable_key":"6cdb37aa-8998-5ea8-829d-4f995caf98fc:l-carnitine-tissue-synthesis-event","event_type":"observed_relationship","label":"Some tissues rely on importing the finished molecule.","description":"Human tissue assays detected gamma-butyrobetaine-to-carnitine activity in liver, kidney and brain, but not heart or skeletal muscle; the earlier steps were detected in all five tissues.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"e83c0395-55f1-5483-9710-9b9aa9767689","slug":"gamma-butyrobetaine","display_name":"gamma-Butyrobetaine","entity_type_key":"small_molecule"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"7d5d7543-391b-50a3-96f8-5e3ca6943f3c","slug":"human-carnitine-biosynthesis-tissue-activity","display_name":"Human tissue carnitine biosynthetic enzyme activity","entity_type_key":"cellular_process"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"6e34c035-9371-578f-b799-fd2a14e9e40f","slug":"l-carnitine","display_name":"L-Carnitine","entity_type_key":"small_molecule"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"2df85b4c-254c-59a1-8fd8-a02cbd3eecd6","slug":"bbox1","display_name":"gamma-Butyrobetaine hydroxylase / BBOX1","entity_type_key":"protein"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""}]},"contexts":[{"dimension":"evidence_access","value_text":"Primary abstract","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Human tissue homogenate enzyme assays.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Detection limits, developmental stage and sampled tissues constrain the result; not an absolute modern atlas.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"L-Carnitine collection; isomer, preparation, species, exposure and manipulation remain explicit.","comparator":null,"unit":null,"notes":"","entity":{"slug":"l-carnitine","display_name":"L-Carnitine","entity_type_key":"small_molecule"}},{"dimension":"plain_language","value_text":"Some tissues rely on importing the finished molecule.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"Tissue distribution of carnitine biosynthetic enzymes in man. · 1980 · https://pubmed.ncbi.nlm.nih.gov/6770910/ · DOI 10.1016/0304-4165(80)90133-6","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"578d93b3-9af3-535e-af4f-dc6c758cb0fc","evidence_kind":"source_excerpt","locator":"Lines 26-32","start_line":26,"end_line":32,"excerpt":"## l-carnitine-tissue-synthesis\nSome tissues rely on importing the finished molecule.\nHuman tissue assays detected gamma-butyrobetaine-to-carnitine activity in liver, kidney and brain, but not heart or skeletal muscle; the earlier steps were detected in all five tissues.\nModel: Human tissue homogenate enzyme assays.\nLimitations: Detection limits, developmental stage and sampled tissues constrain the result; not an absolute modern atlas.\nEvidence access: Primary abstract\nTissue distribution of carnitine biosynthetic enzymes in man. · 1980 · https://pubmed.ncbi.nlm.nih.gov/6770910/ · DOI 10.1016/0304-4165(80)90133-6","model_system":"Human tissue homogenate enzyme assays.","directness":"reported_statement","verification_status":"source_derived_draft","notes":"Original curation paraphrase; evidence access and experimental limitations specified.","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"e2c9c42b-806a-55e2-abde-b0320ea94704","stable_key":"import-6cdb37aa-8998-5ea8-829d-4f995caf98fc","title":"L-Carnitine: synthesis, acyl-group transport, fuel selection and nutrient interactions (2026-09-19)","document_type":"imported_text","citation_label":"AI-assisted research curation; primary-abstract references and experimental limitations individually identified. Not publisher full text.","file_path":"","sha256":"6fcd86d9d02babb48b2ce658d506afe84580ad4b242f93f11f742d934fa5b361","revision_id":"398e3b52-45bc-52e3-891e-656c19ca674f","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}