{"id":"ac37bae7-65c6-539d-ac47-12ef7ddd5f57","stable_key":"4df6a932-097e-563a-91fe-5dceec471ffd:chloride-amylase-geometry","predicate":"stabilizes_catalytic_geometry_of","statement":"Chloride binding influenced E233 positioning and the structural region that orients D300 in pancreatic amylase.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"633be823-70b6-5b5c-a857-2c07db5532b7","mechanism_event_label":"The ion helps position catalytic parts of the enzyme.","subject":{"id":"6f35aa38-f875-5759-b749-97a2f6480ff3","slug":"chloride-ion","display_name":"Chloride ion","entity_type_key":"ion"},"object":{"id":"3cf616ac-0645-5970-8add-872a7d9e1c2f","slug":"amy2a","display_name":"Human pancreatic alpha-amylase / AMY2A","entity_type_key":"protein"},"evidence_count":1,"mechanism_event":{"id":"633be823-70b6-5b5c-a857-2c07db5532b7","stable_key":"4df6a932-097e-563a-91fe-5dceec471ffd:chloride-amylase-geometry-event","event_type":"biochemical_relationship","label":"The ion helps position catalytic parts of the enzyme.","description":"Chloride binding influenced E233 positioning and the structural region that orients D300 in pancreatic amylase.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"6f35aa38-f875-5759-b749-97a2f6480ff3","slug":"chloride-ion","display_name":"Chloride ion","entity_type_key":"ion"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"3cf616ac-0645-5970-8add-872a7d9e1c2f","slug":"amy2a","display_name":"Human pancreatic alpha-amylase / AMY2A","entity_type_key":"protein"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""}]},"contexts":[{"dimension":"evidence_span","value_text":"{\"source_cache\": \"artifacts/chloride-research/15722449.abstract.txt\", \"locator\": \"Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"c71785a489a9e9a0f3865c12c2b66cbf1db4c9e036f08398da846fbb766fbf82\", \"start_char\": 0, \"end_char\": 1748, \"text_sha256\": \"c71785a489a9e9a0f3865c12c2b66cbf1db4c9e036f08398da846fbb766fbf82\"}","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Structure and kinetics","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"N298S variant with and without chloride","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"N298S variant evidence; this is not a claim that all alpha-amylases require chloride.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Chloride research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"chloride","display_name":"Chloride","entity_type_key":"nutrient_element"}},{"dimension":"organism","value_text":"Human pancreatic alpha-amylase variant","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"The ion helps position catalytic parts of the enzyme.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[chloride-p15722449] Structural and mechanistic studies of chloride induced activation of human pancreatic alpha-amylase. (2005). https://pubmed.ncbi.nlm.nih.gov/15722449/ DOI: 10.1110/ps.041079305","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Purified digestive enzyme","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"990dc1c8-e45d-51fb-b231-c367351f1591","evidence_kind":"source_excerpt","locator":"Lines 601-612","start_line":601,"end_line":612,"excerpt":"### chloride-amylase-geometry\nChloride binding influenced E233 positioning and the structural region that orients D300 in pancreatic amylase.\nCondition category: normal\nnutrient_topic: Chloride research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: The ion helps position catalytic parts of the enzyme.\norganism: Human pancreatic alpha-amylase variant\ntissue_or_cell_type: Purified digestive enzyme\nexperimental_model: Structure and kinetics\nlimitations: N298S variant evidence; this is not a claim that all alpha-amylases require chloride.\nexposure: N298S variant with and without chloride\nevidence_span: {\"source_cache\": \"artifacts/chloride-research/15722449.abstract.txt\", \"locator\": \"Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"c71785a489a9e9a0f3865c12c2b66cbf1db4c9e036f08398da846fbb766fbf82\", \"start_char\": 0, \"end_char\": 1748, \"text_sha256\": \"c71785a489a9e9a0f3865c12c2b66cbf1db4c9e036f08398da846fbb766fbf82\"}\n[chloride-p15722449] Structural and mechanistic studies of chloride induced activation of human pancreatic alpha-amylase. (2005). https://pubmed.ncbi.nlm.nih.gov/15722449/ DOI: 10.1110/ps.041079305","model_system":"Structure and kinetics","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [chloride-p15722449] Structural and mechanistic studies of chloride induced activation of human pancreatic alpha-amylase. (2005). https://pubmed.ncbi.nlm.nih.gov/15722449/ DOI: 10.1110/ps.041079305","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"1c2070d5-9f15-5945-b325-d0b49a32c04b","stable_key":"import-4df6a932-097e-563a-91fe-5dceec471ffd","title":"Chloride: transport, acid-base balance, nutrient interactions and loss states (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":"e32e796f293a3287c6b8f4394881db94cc741ba96e3166e44da2dd14f208f645","revision_id":"8d5fd8ef-db54-5198-a368-23329a02d81b","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}