{"id":"311709ef-8ffb-52f7-a5b8-c095cde89c3a","stable_key":"ec174d5a-4903-5745-8646-df0e9d4265e8:folate-brush-border-deconjugation","predicate":"hydrolyzes","statement":"Partially purified human jejunal brush-border folate hydrolase progressively removed glutamates, producing predominantly monoglutamate after 120 minutes.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"positive","is_public":true,"mechanism_event_id":"6b33263b-6632-5152-a2f9-7f6ff8614742","mechanism_event_label":"Food folate tails are shortened before absorption.","subject":{"id":"f75b6059-4033-5997-8b92-acc37f81289d","slug":"folh1","display_name":"Human glutamate carboxypeptidase II / FOLH1","entity_type_key":"protein"},"object":{"id":"81c45abb-713d-521f-9854-23288f880831","slug":"folate-polyglutamates","display_name":"Folate polyglutamates","entity_type_key":"chemical_species"},"evidence_count":1,"mechanism_event":{"id":"6b33263b-6632-5152-a2f9-7f6ff8614742","stable_key":"ec174d5a-4903-5745-8646-df0e9d4265e8:folate-brush-border-deconjugation-event","event_type":"biochemical_relationship","label":"Food folate tails are shortened before absorption.","description":"Partially purified human jejunal brush-border folate hydrolase progressively removed glutamates, producing predominantly monoglutamate after 120 minutes.","status":"provisional","compartment":{"slug":"plasma-membrane","display_name":"Plasma membrane"},"participants":[{"entity":{"id":"f75b6059-4033-5997-8b92-acc37f81289d","slug":"folh1","display_name":"Human glutamate carboxypeptidase II / FOLH1","entity_type_key":"protein"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"81c45abb-713d-521f-9854-23288f880831","slug":"folate-polyglutamates","display_name":"Folate polyglutamates","entity_type_key":"chemical_species"},"role":"object","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"a3d3f56f-92d5-5cb1-a98d-17bad9a3c1c7","slug":"folate-monoglutamates","display_name":"Folate monoglutamates","entity_type_key":"chemical_species"},"role":"product","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"7da684a4-2641-5bc6-93ae-8c6aa384e487","slug":"glutamate","display_name":"L-Glutamate","entity_type_key":"small_molecule"},"role":"released product","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""}]},"contexts":[{"dimension":"experimental_model","value_text":"Partially purified human jejunal brush-border enzyme","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"Radiolabeled synthetic folate polyglutamates in enzyme incubations","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Ex-vivo digestion, not a meal bioavailability measurement.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Folate and folic acid research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"folate","display_name":"Folate (vitamin B9)","entity_type_key":"chemical_species"}},{"dimension":"organism","value_text":"Homo sapiens","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"Food folate tails are shortened before absorption.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[reisenauer1981] Human jejunal brush border folate conjugase. Characteristics and inhibition by salicylazosulfapyridine (1981). https://pubmed.ncbi.nlm.nih.gov/6113848/ DOI: 10.1016/0005-2744(81)90271-0","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Jejunal brush border","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"9da32a6a-4e8a-570b-ab31-880cac775e02","evidence_kind":"source_excerpt","locator":"Lines 82-92","start_line":82,"end_line":92,"excerpt":"### folate-brush-border-deconjugation\nPartially purified human jejunal brush-border folate hydrolase progressively removed glutamates, producing predominantly monoglutamate after 120 minutes.\nCondition category: normal\nnutrient_topic: Folate and folic acid research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Food folate tails are shortened before absorption.\norganism: Homo sapiens\ntissue_or_cell_type: Jejunal brush border\nexperimental_model: Partially purified human jejunal brush-border enzyme\nlimitations: Ex-vivo digestion, not a meal bioavailability measurement.\nexposure: Radiolabeled synthetic folate polyglutamates in enzyme incubations\n[reisenauer1981] Human jejunal brush border folate conjugase. Characteristics and inhibition by salicylazosulfapyridine (1981). https://pubmed.ncbi.nlm.nih.gov/6113848/ DOI: 10.1016/0005-2744(81)90271-0","model_system":"Partially purified human jejunal brush-border enzyme","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [reisenauer1981] Human jejunal brush border folate conjugase. Characteristics and inhibition by salicylazosulfapyridine (1981). https://pubmed.ncbi.nlm.nih.gov/6113848/ DOI: 10.1016/0005-2744(81)90271-0","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"f4ce1a62-9582-5f7a-84f5-a23d0e1bfc68","stable_key":"import-ec174d5a-4903-5745-8646-df0e9d4265e8","title":"Folate and folic acid: 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":"e564d43989ece1006c95cd0748e9af6fe369074599a2eebba0a99ebff864b0dd","revision_id":"76674a33-b2a1-5e41-b71b-44399038ff7c","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}