{"id":"0a69e08a-20a7-5764-9015-74bbf9876234","stable_key":"1310afbd-6010-586e-805d-551d846da421:b6-neuro-spt-sphingolipid-entry","predicate":"produces","statement":"PLP-dependent human SPT condenses serine and palmitoyl-CoA into 3-ketosphinganine; the product-bound structure locates its headgroup and acyl chain.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"positive","is_public":true,"mechanism_event_id":"2106c3b2-261d-52c4-97cf-00770d18c94b","mechanism_event_label":"B6 supports entry into sphingolipid synthesis.","subject":{"id":"25fd8f94-278f-5967-ba2c-37debeae2e65","slug":"human-serine-palmitoyltransferase-complex","display_name":"Human SPTLC1-SPTLC2-SPTSSA complex","entity_type_key":"protein_complex"},"object":{"id":"b25555ef-cb00-56e2-b7eb-846b4fa49ea2","slug":"3-ketosphinganine","display_name":"3-Ketosphinganine","entity_type_key":"lipid"},"evidence_count":1,"mechanism_event":{"id":"2106c3b2-261d-52c4-97cf-00770d18c94b","stable_key":"1310afbd-6010-586e-805d-551d846da421:b6-neuro-spt-sphingolipid-entry-event","event_type":"biochemical_relationship","label":"B6 supports entry into sphingolipid synthesis.","description":"PLP-dependent human SPT condenses serine and palmitoyl-CoA into 3-ketosphinganine; 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no intact tissue","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"6dc5b710-dfaa-52ce-847f-f21aae5b139c","evidence_kind":"source_excerpt","locator":"Lines 1120-1131","start_line":1120,"end_line":1131,"excerpt":"### b6-neuro-spt-sphingolipid-entry\nPLP-dependent human SPT condenses serine and palmitoyl-CoA into 3-ketosphinganine; the product-bound structure locates its headgroup and acyl chain.\nCondition category: normal\nnutrient_topic: Vitamin B6 research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: B6 supports entry into sphingolipid synthesis.\norganism: Homo sapiens\ntissue_or_cell_type: Purified recombinant protein; no intact tissue\nexperimental_model: Recombinant human SPT complexes; cryo-EM and cell/microsome activity assays\nlimitations: Does not show that B6 supplementation repairs myelin.\nexposure: Product-bound cryo-EM and functional enzyme assays.\ncross_nutrient: B6-dependent use of the amino acid serine and a fatty-acyl-CoA substrate.\n[wang-2021-spt] Structural insights into the regulation of human serine palmitoyltransferase complexes (2021). https://pmc.ncbi.nlm.nih.gov/articles/PMC9812531/ DOI: 10.1038/s41594-020-00551-9","model_system":"Recombinant human SPT complexes; 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Study references: [wang-2021-spt] Structural insights into the regulation of human serine palmitoyltransferase complexes (2021). https://pmc.ncbi.nlm.nih.gov/articles/PMC9812531/ DOI: 10.1038/s41594-020-00551-9","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"251773bb-16f5-5903-b135-db4a61d9dec4","stable_key":"import-1310afbd-6010-586e-805d-551d846da421","title":"Vitamin B6: 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":"ef0019b344b2219220f801a84d0d138ff6880c1be1a59540d9034bfa4334f61e","revision_id":"cac3555f-48af-5c52-a84e-add4482c87fb","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}