{"id":"f457db40-0868-5457-bed5-51c2b8dba9da","stable_key":"6cdb37aa-8998-5ea8-829d-4f995caf98fc:l-carnitine-aldehyde-step","predicate":"oxidizes_to","statement":"Expressing human ALDH9 in bacteria produced NAD+-dependent trimethylaminobutyraldehyde dehydrogenase activity, completing the aldehyde-to-gamma-butyrobetaine step.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"eee69232-7249-5e46-bb09-1dd408f059b9","mechanism_event_label":"A niacin-derived coenzyme participates in making carnitine.","subject":{"id":"c31af957-2ab3-5b80-b389-8989755433e4","slug":"aldh9a1","display_name":"ALDH9A1","entity_type_key":"protein"},"object":{"id":"e83c0395-55f1-5483-9710-9b9aa9767689","slug":"gamma-butyrobetaine","display_name":"gamma-Butyrobetaine","entity_type_key":"small_molecule"},"evidence_count":1,"mechanism_event":{"id":"eee69232-7249-5e46-bb09-1dd408f059b9","stable_key":"6cdb37aa-8998-5ea8-829d-4f995caf98fc:l-carnitine-aldehyde-step-event","event_type":"observed_relationship","label":"A niacin-derived coenzyme participates in making carnitine.","description":"Expressing human ALDH9 in bacteria produced NAD+-dependent trimethylaminobutyraldehyde dehydrogenase activity, completing the aldehyde-to-gamma-butyrobetaine step.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"c31af957-2ab3-5b80-b389-8989755433e4","slug":"aldh9a1","display_name":"ALDH9A1","entity_type_key":"protein"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"e83c0395-55f1-5483-9710-9b9aa9767689","slug":"gamma-butyrobetaine","display_name":"gamma-Butyrobetaine","entity_type_key":"small_molecule"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"b11e7a9c-d4c0-5f9e-92d1-9f1ca432bab3","slug":"trimethylaminobutyraldehyde","display_name":"4-Trimethylaminobutyraldehyde","entity_type_key":"small_molecule"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"283ed24b-06a1-50aa-9281-df3bac6ce37e","slug":"nad-plus","display_name":"NAD+","entity_type_key":"small_molecule"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":3,"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":4,"notes":""}]},"contexts":[{"dimension":"evidence_access","value_text":"Primary abstract","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Recombinant human ALDH9 compared with purified and recombinant rat enzyme.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"NAD+ dependence does not establish benefit from niacin supplementation.","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":"A niacin-derived coenzyme participates in making carnitine.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"Molecular and biochemical characterization of rat gamma-trimethylaminobutyraldehyde dehydrogenase and evidence for the involvement of human aldehyde dehydrogenase 9 in carnitine biosynthesis. · 2000 · https://pubmed.ncbi.nlm.nih.gov/10702312/ · DOI 10.1074/jbc.275.10.7390","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"05fb4747-f557-50ab-9a3e-5647f7a0fdeb","evidence_kind":"source_excerpt","locator":"Lines 18-24","start_line":18,"end_line":24,"excerpt":"## l-carnitine-aldehyde-step\nA niacin-derived coenzyme participates in making carnitine.\nExpressing human ALDH9 in bacteria produced NAD+-dependent trimethylaminobutyraldehyde dehydrogenase activity, completing the aldehyde-to-gamma-butyrobetaine step.\nModel: Recombinant human ALDH9 compared with purified and recombinant rat enzyme.\nLimitations: NAD+ dependence does not establish benefit from niacin supplementation.\nEvidence access: Primary abstract\nMolecular and biochemical characterization of rat gamma-trimethylaminobutyraldehyde dehydrogenase and evidence for the involvement of human aldehyde dehydrogenase 9 in carnitine biosynthesis. · 2000 · https://pubmed.ncbi.nlm.nih.gov/10702312/ · DOI 10.1074/jbc.275.10.7390","model_system":"Recombinant human ALDH9 compared with purified and recombinant rat enzyme.","directness":"reported_statement","verification_status":"source_derived_draft","notes":"Original curation paraphrase; 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