{"id":"057488eb-7186-55df-bd6a-2882b27c762c","stable_key":"4fef8d72-f107-5eb5-b2fb-483ca85465e0:k2-mk4-nad-catabolism","predicate":"supports_dehydrogenase_conversion_of","statement":"Microsomal NAD-dependent alcohol and aldehyde dehydrogenase activities converted the MK-4 omega-alcohol to its acid.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"f9aca2a6-7138-506f-902f-4ac69ff58853","mechanism_event_label":"Niacin-derived NAD participates in an alternative route through the breakdown sequence.","subject":{"id":"283ed24b-06a1-50aa-9281-df3bac6ce37e","slug":"nad-plus","display_name":"NAD+","entity_type_key":"small_molecule"},"object":{"id":"519e2477-b652-566d-b7f8-72d00e5672b2","slug":"mk4-omega-alcohol","display_name":"Omega-hydroxymenaquinone-4","entity_type_key":"small_molecule"},"evidence_count":1,"mechanism_event":{"id":"f9aca2a6-7138-506f-902f-4ac69ff58853","stable_key":"4fef8d72-f107-5eb5-b2fb-483ca85465e0:k2-mk4-nad-catabolism-event","event_type":"biochemical_relationship","label":"Niacin-derived NAD participates in an alternative route through the breakdown sequence.","description":"Microsomal NAD-dependent alcohol and aldehyde dehydrogenase activities converted the MK-4 omega-alcohol to its acid.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"a065424f-ac9b-507f-93d6-9fcffb38fb0c","slug":"mk4-omega-acid","display_name":"Menaquinone-4 omega-carboxylic acid","entity_type_key":"small_molecule"},"role":"product","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"283ed24b-06a1-50aa-9281-df3bac6ce37e","slug":"nad-plus","display_name":"NAD+","entity_type_key":"small_molecule"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"519e2477-b652-566d-b7f8-72d00e5672b2","slug":"mk4-omega-alcohol","display_name":"Omega-hydroxymenaquinone-4","entity_type_key":"small_molecule"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""}]},"contexts":[{"dimension":"evidence_span","value_text":"{\"source_cache\": \"artifacts/k2-research/24138531.abstract.txt\", \"locator\": \"Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"bcb3784026ddabfeb55257cddc84ffd1001d6eb4fb04ba2e9daf8ade8de770fb\", \"start_char\": 0, \"end_char\": 1608, \"text_sha256\": \"bcb3784026ddabfeb55257cddc84ffd1001d6eb4fb04ba2e9daf8ade8de770fb\"}","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Purified enzymes, liver microsomes and genotyping","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"MK-4 oxidation and common enzyme variants","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Catabolism assay; no assumption that all long-chain menaquinones have identical kinetics.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Vitamin K2 research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"k2","display_name":"Vitamin K2 / menaquinone family","entity_type_key":"chemical_species"}},{"dimension":"organism","value_text":"Human CYP4F2/CYP4F11 and human liver microsomes","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"Niacin-derived NAD participates in an alternative route through the breakdown sequence.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[k2-p24138531] Cytochrome P450-dependent catabolism of vitamin K: ω-hydroxylation catalyzed by human CYP4F2 and CYP4F11. (2013). https://pubmed.ncbi.nlm.nih.gov/24138531/ DOI: 10.1021/bi401208m","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"MK-4 catabolism","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"06498b01-2fb2-599b-ac59-03e90eafd0b5","evidence_kind":"source_excerpt","locator":"Lines 357-368","start_line":357,"end_line":368,"excerpt":"### k2-mk4-nad-catabolism\nMicrosomal NAD-dependent alcohol and aldehyde dehydrogenase activities converted the MK-4 omega-alcohol to its acid.\nCondition category: normal\nnutrient_topic: Vitamin K2 research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Niacin-derived NAD participates in an alternative route through the breakdown sequence.\norganism: Human CYP4F2/CYP4F11 and human liver microsomes\ntissue_or_cell_type: MK-4 catabolism\nexperimental_model: Purified enzymes, liver microsomes and genotyping\nlimitations: Catabolism assay; no assumption that all long-chain menaquinones have identical kinetics.\nexposure: MK-4 oxidation and common enzyme variants\nevidence_span: {\"source_cache\": \"artifacts/k2-research/24138531.abstract.txt\", \"locator\": \"Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"bcb3784026ddabfeb55257cddc84ffd1001d6eb4fb04ba2e9daf8ade8de770fb\", \"start_char\": 0, \"end_char\": 1608, \"text_sha256\": \"bcb3784026ddabfeb55257cddc84ffd1001d6eb4fb04ba2e9daf8ade8de770fb\"}\n[k2-p24138531] Cytochrome P450-dependent catabolism of vitamin K: ω-hydroxylation catalyzed by human CYP4F2 and CYP4F11. 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