{"id":"06f3a79d-863f-513e-8495-60c3aa4e518c","stable_key":"6d38d43e-01e4-5641-93be-65654271e242:zinc-enz-ca6-hydration","predicate":"catalyzes_formation_of","statement":"Purified human salivary and milk CA6 catalyzed CO2 hydration, with reported kcat values of 3.3×10^5 and 2.3×10^5 s−1, respectively.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"positive","is_public":true,"mechanism_event_id":"ef58f3ef-dee0-55ed-b7b0-62ddb4af249d","mechanism_event_label":"Secreted CA6 accelerates conversion of carbon dioxide and water into bicarbonate.","subject":{"id":"1702b00c-5ca3-56bb-9136-503543f60dae","slug":"ca6","display_name":"Human carbonic anhydrase VI / CA6","entity_type_key":"protein"},"object":{"id":"edf44f6b-7b23-5b97-a86b-c940e5812b06","slug":"bicarbonate-ion","display_name":"Bicarbonate ion","entity_type_key":"ion"},"evidence_count":1,"mechanism_event":{"id":"ef58f3ef-dee0-55ed-b7b0-62ddb4af249d","stable_key":"6d38d43e-01e4-5641-93be-65654271e242:zinc-enz-ca6-hydration-event","event_type":"biochemical_relationship","label":"Secreted CA6 accelerates conversion of carbon dioxide and water into bicarbonate.","description":"Purified human salivary and milk CA6 catalyzed CO2 hydration, with reported kcat values of 3.3×10^5 and 2.3×10^5 s−1, respectively.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"966f14e5-c82f-5535-ad89-bfcc0adb2232","slug":"carbon-dioxide","display_name":"Carbon dioxide","entity_type_key":"small_molecule"},"role":"substrate","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"d31225b7-8e94-5857-9ea1-67ac794b1f15","slug":"water","display_name":"H2O","entity_type_key":"small_molecule"},"role":"substrate","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"1ed0233a-3d10-58b3-abda-8ad04545c495","slug":"proton","display_name":"Proton","entity_type_key":"ion"},"role":"product","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"49c806c2-7041-5020-8b3b-fa04ffa122ac","slug":"zinc-ion","display_name":"Zinc(II) ion","entity_type_key":"ion"},"role":"enzyme_cofactor","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""},{"entity":{"id":"1702b00c-5ca3-56bb-9136-503543f60dae","slug":"ca6","display_name":"Human carbonic anhydrase VI / CA6","entity_type_key":"protein"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":4,"notes":""},{"entity":{"id":"edf44f6b-7b23-5b97-a86b-c940e5812b06","slug":"bicarbonate-ion","display_name":"Bicarbonate ion","entity_type_key":"ion"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":5,"notes":""}]},"contexts":[{"dimension":"cross_nutrient","value_text":"false","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Human CA6 purified from pooled saliva or breast milk; stopped-flow enzymology","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"Stopped-flow CO2 hydration assay of proteins purified from pooled human saliva and milk.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Protein kinetic measurements; no test of dietary zinc treatment or infant health outcomes. Table values characterize the isolated preparations.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Zinc research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"zinc","display_name":"Zinc","entity_type_key":"nutrient_element"}},{"dimension":"organism","value_text":"Homo sapiens","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"Secreted CA6 accelerates conversion of carbon dioxide and water into bicarbonate.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[zinc-enz-ca6-2022] Biochemical and Biophysical Characterization of Carbonic Anhydrase VI from Human Milk and Saliva. (2022). https://pubmed.ncbi.nlm.nih.gov/35947329/ DOI: 10.1007/s10930-022-10070-9","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Human saliva and breast milk; purified enzyme assay","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"d732cc62-acf4-5b50-8d69-13b9357b6b9d","evidence_kind":"source_excerpt","locator":"Lines 664-675","start_line":664,"end_line":675,"excerpt":"### zinc-enz-ca6-hydration\nPurified human salivary and milk CA6 catalyzed CO2 hydration, with reported kcat values of 3.3×10^5 and 2.3×10^5 s−1, respectively.\nCondition category: normal\nnutrient_topic: Zinc research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Secreted CA6 accelerates conversion of carbon dioxide and water into bicarbonate.\norganism: Homo sapiens\ntissue_or_cell_type: Human saliva and breast milk; purified enzyme assay\nexperimental_model: Human CA6 purified from pooled saliva or breast milk; stopped-flow enzymology\nlimitations: Protein kinetic measurements; no test of dietary zinc treatment or infant health outcomes. Table values characterize the isolated preparations.\nexposure: Stopped-flow CO2 hydration assay of proteins purified from pooled human saliva and milk.\ncross_nutrient: false\n[zinc-enz-ca6-2022] Biochemical and Biophysical Characterization of Carbonic Anhydrase VI from Human Milk and Saliva. (2022). https://pubmed.ncbi.nlm.nih.gov/35947329/ DOI: 10.1007/s10930-022-10070-9","model_system":"Human CA6 purified from pooled saliva or breast milk; stopped-flow enzymology","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [zinc-enz-ca6-2022] Biochemical and Biophysical Characterization of Carbonic Anhydrase VI from Human Milk and Saliva. (2022). https://pubmed.ncbi.nlm.nih.gov/35947329/ DOI: 10.1007/s10930-022-10070-9","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"c5ee0fee-ce5c-58de-905a-10fb0ea0723c","stable_key":"import-6d38d43e-01e4-5641-93be-65654271e242","title":"Zinc: transport, enzyme loading, 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":"2e731dd54477ec1254e97df3323e1208d38f1375effed19252e71ab4f600d13a","revision_id":"c72258b9-ac09-5408-9d44-a921ad1f96a3","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}