{"id":"2d03679d-2ce1-5c6e-ab6f-5922d63258e0","stable_key":"649e861b-265a-5912-bc36-3a73e53ef892:l-serine-nadhx-inhibition","predicate":"inhibits","statement":"Purified NADHX species inhibited recombinant human PHGDH, supporting direct inhibition as an explanation for the serine-synthesis defect in NAXD-deficient cells.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"negative","is_public":true,"mechanism_event_id":"5074e91d-0410-5306-a97f-97355393fea9","mechanism_event_label":"Repair of a niacin-derived cofactor protects a separate amino-acid pathway.","subject":{"id":"a1653234-1f4f-5161-9b9f-53a68bdff6c3","slug":"nadhx","display_name":"Hydrated NADH / NADHX","entity_type_key":"small_molecule"},"object":{"id":"bde7376b-95ef-5b84-8789-353ec30d5b9b","slug":"phgdh","display_name":"Human phosphoglycerate dehydrogenase / PHGDH","entity_type_key":"protein"},"evidence_count":1,"mechanism_event":{"id":"5074e91d-0410-5306-a97f-97355393fea9","stable_key":"649e861b-265a-5912-bc36-3a73e53ef892:l-serine-nadhx-inhibition-event","event_type":"observed_relationship","label":"Repair of a niacin-derived cofactor protects a separate amino-acid pathway.","description":"Purified NADHX species inhibited recombinant human PHGDH, supporting direct inhibition as an explanation for the serine-synthesis defect in NAXD-deficient cells.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"a1653234-1f4f-5161-9b9f-53a68bdff6c3","slug":"nadhx","display_name":"Hydrated NADH / NADHX","entity_type_key":"small_molecule"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"bde7376b-95ef-5b84-8789-353ec30d5b9b","slug":"phgdh","display_name":"Human phosphoglycerate dehydrogenase / PHGDH","entity_type_key":"protein"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"c882cd0b-9d83-5b07-bd1c-fe4d45657dcb","slug":"l-serine","display_name":"L-Serine","entity_type_key":"small_molecule"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"7120d12b-1691-55fc-bec5-d42f857b44ca","slug":"3-phosphoglycerate","display_name":"3-Phosphoglycerate","entity_type_key":"small_molecule"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""},{"entity":{"id":"9fbf2e03-16a9-5ca7-965c-0bfc07ca24da","slug":"nadh","display_name":"NADH","entity_type_key":"small_molecule"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":4,"notes":""}]},"contexts":[{"dimension":"evidence_access","value_text":"Primary full text","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Recombinant enzyme assays, including 40 micromolar 3-phosphoglycerate substrate.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"NADHX is chemically damaged NADH, not simply a low NAD+ concentration.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"L-Serine collection; 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