{"id":"a9f775e4-5d99-5976-92d1-f6b868e55f9c","stable_key":"ea2f0904-ab2c-5d1e-a3d4-3f7ecdd70cd6:caf-a2a-structure","predicate":"binds","statement":"Crystallography resolved caffeine in a thermostabilized A2A receptor with an inactive-state conformation.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"abf4d5b1-e10b-5699-9c6d-0fabd01777a0","mechanism_event_label":"A receptor structure shows where caffeine binds.","subject":{"id":"ef028472-7c33-583d-b52e-40676004d370","slug":"caffeine","display_name":"Caffeine","entity_type_key":"small_molecule"},"object":{"id":"2cfb6c87-5a4d-5d70-b908-52c80191f7ec","slug":"adora2a-thermostabilized","display_name":"Thermostabilized human A2A receptor crystallography construct","entity_type_key":"protein_state"},"evidence_count":1,"mechanism_event":{"id":"abf4d5b1-e10b-5699-9c6d-0fabd01777a0","stable_key":"ea2f0904-ab2c-5d1e-a3d4-3f7ecdd70cd6:caf-a2a-structure-event","event_type":"observed_relationship","label":"A receptor structure shows where caffeine binds.","description":"Crystallography resolved caffeine in a thermostabilized A2A receptor with an inactive-state conformation.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"ef028472-7c33-583d-b52e-40676004d370","slug":"caffeine","display_name":"Caffeine","entity_type_key":"small_molecule"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"2cfb6c87-5a4d-5d70-b908-52c80191f7ec","slug":"adora2a-thermostabilized","display_name":"Thermostabilized human A2A receptor crystallography construct","entity_type_key":"protein_state"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"6bebe966-e8de-5a69-aa15-8e651fc58e10","slug":"adora2a","display_name":"Human adenosine A2A receptor / ADORA2A","entity_type_key":"protein"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"b1001072-f1ab-54a1-80fd-d15a41e31adb","slug":"adenosine","display_name":"Adenosine","entity_type_key":"small_molecule"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""}]},"contexts":[{"dimension":"evidence_access","value_text":"Primary abstract","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Engineered human receptor construct; crystallographic comparison with XAC and ZM241385.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Engineered inactive-state structure, not a measurement of native receptor signaling in a person.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Caffeine collection; salts, coffee, species and coexposure contexts retain their identities.","comparator":null,"unit":null,"notes":"","entity":{"slug":"caffeine","display_name":"Caffeine","entity_type_key":"small_molecule"}},{"dimension":"plain_language","value_text":"A receptor structure shows where caffeine binds.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"Structure of the adenosine A(2A) receptor in complex with ZM241385 and the xanthines XAC and caffeine. · 2011 · https://pubmed.ncbi.nlm.nih.gov/21885291/ · DOI 10.1016/j.str.2011.06.014","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"dc43f5cf-9440-5907-b4b1-a38932d2cb2e","evidence_kind":"source_excerpt","locator":"Lines 28-34","start_line":28,"end_line":34,"excerpt":"## caf-a2a-structure\nA receptor structure shows where caffeine binds.\nCrystallography resolved caffeine in a thermostabilized A2A receptor with an inactive-state conformation.\nModel: Engineered human receptor construct; crystallographic comparison with XAC and ZM241385.\nLimitations: Engineered inactive-state structure, not a measurement of native receptor signaling in a person.\nEvidence access: Primary abstract\nStructure of the adenosine A(2A) receptor in complex with ZM241385 and the xanthines XAC and caffeine. · 2011 · https://pubmed.ncbi.nlm.nih.gov/21885291/ · DOI 10.1016/j.str.2011.06.014","model_system":"Engineered human receptor construct; crystallographic comparison with XAC and ZM241385.","directness":"reported_statement","verification_status":"source_derived_draft","notes":"Original curation paraphrase; evidence access stated with the claim.","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"40a654db-878c-5471-bc6c-88f4f52599c0","stable_key":"import-ea2f0904-ab2c-5d1e-a3d4-3f7ecdd70cd6","title":"Caffeine: receptors, metabolism, nutrient interactions, adaptation and discovery questions (2026-09-18)","document_type":"imported_text","citation_label":"AI-assisted research curation; primary-abstract references and experimental limitations individually identified. Not publisher full text.","file_path":"","sha256":"780d73d4abd45a0284d2cc0c646dbe8432ae347362891a4b98a19a61341a7325","revision_id":"f36ffb0a-d6df-522f-b783-5e30214b9e26","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}