{"id":"22ce6c53-2488-5ae3-9425-ddb1b3903a17","stable_key":"cb568d28-484a-5c2e-9fcc-2d780358e514:vc-transport-bovine-pdi-dha","predicate":"catalyzes-reduction-of","statement":"Purified bovine liver protein disulfide isomerase catalyzed DHA reduction with GSH; apparent DHA Km was 1.0 mM.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"positive","is_public":true,"mechanism_event_id":"4f872261-5290-5c45-ad26-e060965ad689","mechanism_event_label":"A bovine protein-folding enzyme also recycled oxidized vitamin C in a purified assay.","subject":{"id":"8b7b5910-385d-5e12-a5a7-d46a71035d00","slug":"bovine-p4hb","display_name":"Bovine protein disulfide isomerase / P4HB","entity_type_key":"protein"},"object":{"id":"e6658c2b-ccff-5122-80a5-2e153f12ba90","slug":"dehydroascorbic-acid","display_name":"Dehydroascorbic acid","entity_type_key":"small_molecule"},"evidence_count":1,"mechanism_event":{"id":"4f872261-5290-5c45-ad26-e060965ad689","stable_key":"cb568d28-484a-5c2e-9fcc-2d780358e514:vc-transport-bovine-pdi-dha-event","event_type":"biochemical_relationship","label":"A bovine protein-folding enzyme also recycled oxidized vitamin C in a purified assay.","description":"Purified bovine liver protein disulfide isomerase catalyzed DHA reduction with GSH; apparent DHA Km was 1.0 mM.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"b44c9e27-4bbb-52d3-a022-14cddded5073","slug":"glutathione","display_name":"GSH","entity_type_key":"small_molecule"},"role":"electron donor","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"38d0c4d9-53d1-5239-bfe3-c1b5e9b79085","slug":"ascorbate","display_name":"L-Ascorbate","entity_type_key":"small_molecule"},"role":"product","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"8b7b5910-385d-5e12-a5a7-d46a71035d00","slug":"bovine-p4hb","display_name":"Bovine protein disulfide isomerase / P4HB","entity_type_key":"protein"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"e6658c2b-ccff-5122-80a5-2e153f12ba90","slug":"dehydroascorbic-acid","display_name":"Dehydroascorbic acid","entity_type_key":"small_molecule"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""}]},"contexts":[{"dimension":"cross_nutrient","value_text":"true","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Purified human placental glutaredoxin and bovine liver PDI; additional porcine/bovine glutaredoxins","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"Purified PDI, DHA and GSH","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Do not infer intact human endoplasmic-reticulum flux from this enzyme-capacity result.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Vitamin C research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"vitamin-c","display_name":"Vitamin C","entity_type_key":"chemical_species"}},{"dimension":"organism","value_text":"Bos taurus","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"A bovine protein-folding enzyme also recycled oxidized vitamin C in a purified assay.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[wells1990] Mammalian thioltransferase (glutaredoxin) and protein disulfide isomerase have dehydroascorbate reductase activity. (1990). https://pubmed.ncbi.nlm.nih.gov/2394726/ DOI: 10.1016/s0021-9258(18)55401-6","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Liver enzyme preparation","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"c82bdaf2-6e50-589d-8b1b-d77f4a0c4bbe","evidence_kind":"source_excerpt","locator":"Lines 364-375","start_line":364,"end_line":375,"excerpt":"### vc-transport-bovine-pdi-dha\nPurified bovine liver protein disulfide isomerase catalyzed DHA reduction with GSH; apparent DHA Km was 1.0 mM.\nCondition category: normal\nnutrient_topic: Vitamin C research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: A bovine protein-folding enzyme also recycled oxidized vitamin C in a purified assay.\norganism: Bos taurus\ntissue_or_cell_type: Liver enzyme preparation\nexperimental_model: Purified human placental glutaredoxin and bovine liver PDI; additional porcine/bovine glutaredoxins\nlimitations: Do not infer intact human endoplasmic-reticulum flux from this enzyme-capacity result.\nexposure: Purified PDI, DHA and GSH\ncross_nutrient: true\n[wells1990] Mammalian thioltransferase (glutaredoxin) and protein disulfide isomerase have dehydroascorbate reductase activity. 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