{"id":"53b2d122-c896-5f3d-a78f-0cd4ef5829db","stable_key":"46d15d9e-d3b5-544d-ba01-b785aa3e4f42:b1-phosphate-ester-hydrolysis","predicate":"catalyzes","statement":"Calf intestinal alkaline phosphatase hydrolyzed ThDP and ThMP; ThDP had 53-fold higher Vmax/Km under the tested conditions.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"positive","is_public":true,"mechanism_event_id":"a21ffef8-ccf7-5858-b42d-aed9009f82a8","mechanism_event_label":"An intestinal enzyme can remove B1 phosphate groups; the two forms react at different rates.","subject":{"id":"7b7a4921-279c-53dd-805b-038ef0fd26f9","slug":"calf-intestinal-alkaline-phosphatase","display_name":"Calf intestinal alkaline phosphatase","entity_type_key":"protein"},"object":{"id":"51758d15-cfd9-5b8b-bb5e-37c538ee9845","slug":"thiamine-phosphate-hydrolysis","display_name":"Thiamine phosphate ester hydrolysis","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"a21ffef8-ccf7-5858-b42d-aed9009f82a8","stable_key":"46d15d9e-d3b5-544d-ba01-b785aa3e4f42:b1-phosphate-ester-hydrolysis-event","event_type":"biochemical_relationship","label":"An intestinal enzyme can remove B1 phosphate groups; the two forms react at different rates.","description":"Calf intestinal alkaline phosphatase hydrolyzed ThDP and ThMP; ThDP had 53-fold higher Vmax/Km under the tested conditions.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"187db168-8028-5ce6-9f8b-4bc61ebad1a0","slug":"thiamine-diphosphate","display_name":"Thiamine diphosphate","entity_type_key":"small_molecule"},"role":"substrate","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"2d52919c-025a-5772-92b0-6229c0b74ba3","slug":"thiamine-monophosphate","display_name":"Thiamine monophosphate","entity_type_key":"small_molecule"},"role":"substrate","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"7b7a4921-279c-53dd-805b-038ef0fd26f9","slug":"calf-intestinal-alkaline-phosphatase","display_name":"Calf intestinal alkaline phosphatase","entity_type_key":"protein"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"51758d15-cfd9-5b8b-bb5e-37c538ee9845","slug":"thiamine-phosphate-hydrolysis","display_name":"Thiamine phosphate ester hydrolysis","entity_type_key":"cellular_process"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""}]},"contexts":[{"dimension":"evidence-scope","value_text":"Purified intestinal enzyme","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"evidence_locator","value_text":"Abstract","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"evidence_spans","value_text":"[{\"source_document\": \"artifacts/thiamine_transport_sources/vovk-2002-phosphatase-source-record.json\", \"source_field\": \"resultList.result[0].abstractText\", \"start_char\": 0, \"end_char\": 828}]","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Calf intestinal alkaline phosphatase; pH 8.5, 30 C; substrate kinetics.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Purified bovine enzyme; does not quantify human meal absorption.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Thiamine research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"thiamine","display_name":"Thiamine (vitamin B1)","entity_type_key":"small_molecule"}},{"dimension":"organism","value_text":"Bos taurus","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"An intestinal enzyme can remove B1 phosphate groups; the two forms react at different rates.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[vovk-2002-phosphatase] [Relative reactivity of thiamine monophosphate and thiamine diphosphate upon interaction with alkaline phosphatase] (2002). https://pubmed.ncbi.nlm.nih.gov/12199107/","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Purified intestinal enzyme","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"ab5291ca-07b1-50aa-8947-3c526c9c45aa","evidence_kind":"source_excerpt","locator":"Lines 106-118","start_line":106,"end_line":118,"excerpt":"### b1-phosphate-ester-hydrolysis\nCalf intestinal alkaline phosphatase hydrolyzed ThDP and ThMP; ThDP had 53-fold higher Vmax/Km under the tested conditions.\nCondition category: normal\nnutrient_topic: Thiamine research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: An intestinal enzyme can remove B1 phosphate groups; the two forms react at different rates.\norganism: Bos taurus\ntissue_or_cell_type: Purified intestinal enzyme\nexperimental_model: Calf intestinal alkaline phosphatase; pH 8.5, 30 C; substrate kinetics.\nlimitations: Purified bovine enzyme; does not quantify human meal absorption.\nevidence_spans: [{\"source_document\": \"artifacts/thiamine_transport_sources/vovk-2002-phosphatase-source-record.json\", \"source_field\": \"resultList.result[0].abstractText\", \"start_char\": 0, \"end_char\": 828}]\nevidence_locator: Abstract\nevidence-scope: Purified intestinal enzyme\n[vovk-2002-phosphatase] [Relative reactivity of thiamine monophosphate and thiamine diphosphate upon interaction with alkaline phosphatase] (2002). https://pubmed.ncbi.nlm.nih.gov/12199107/","model_system":"Calf intestinal alkaline phosphatase; pH 8.5, 30 C; substrate kinetics.","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [vovk-2002-phosphatase] [Relative reactivity of thiamine monophosphate and thiamine diphosphate upon interaction with alkaline phosphatase] (2002). https://pubmed.ncbi.nlm.nih.gov/12199107/","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"158d2c03-ac8c-589f-8270-c468165ae346","stable_key":"import-46d15d9e-d3b5-544d-ba01-b785aa3e4f42","title":"Thiamine: 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":"f376512fb3310141315548015b387833e3af45146e73fb73cd02cee20e4ddb9c","revision_id":"53bc5eda-dec8-58cc-a56f-a9eb4ab036ef","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}