{"id":"1136d492-c1d5-5891-ab8a-e937b8dfd397","stable_key":"d8050016-13c9-5391-9d61-63de73590053:zeaxanthin-membrane-orientation","predicate":"spans","statement":"Zeaxanthin adopted a transmembrane orientation in the DMPC bilayer, with mean tilt near 40 degrees to the membrane normal.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"de9a879b-d6d1-500f-8816-7f6748be548f","mechanism_event_label":"The pigment spans the membrane rather than remaining only on its surface.","subject":{"id":"0a60c685-7502-5ece-9da2-2c1a2e3bcdf1","slug":"zeaxanthin","display_name":"Dietary (3R,3-prime-R)-zeaxanthin","entity_type_key":"small_molecule"},"object":{"id":"fed26a58-4882-548c-8d14-d8fc804c0971","slug":"dmpc-bilayer","display_name":"Dimyristoylphosphatidylcholine model bilayer","entity_type_key":"chemical_species"},"evidence_count":1,"mechanism_event":{"id":"de9a879b-d6d1-500f-8816-7f6748be548f","stable_key":"d8050016-13c9-5391-9d61-63de73590053:zeaxanthin-membrane-orientation-event","event_type":"biochemical_relationship","label":"The pigment spans the membrane rather than remaining only on its surface.","description":"Zeaxanthin adopted a transmembrane orientation in the DMPC bilayer, with mean tilt near 40 degrees to the membrane normal.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"5dd84367-3f8e-5a3f-b952-a96174ea51fa","slug":"lutein","display_name":"Lutein","entity_type_key":"small_molecule"},"role":"comparison_carotenoid","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"0a60c685-7502-5ece-9da2-2c1a2e3bcdf1","slug":"zeaxanthin","display_name":"Dietary (3R,3-prime-R)-zeaxanthin","entity_type_key":"small_molecule"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"fed26a58-4882-548c-8d14-d8fc804c0971","slug":"dmpc-bilayer","display_name":"Dimyristoylphosphatidylcholine model bilayer","entity_type_key":"chemical_species"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""}]},"contexts":[{"dimension":"evidence_span","value_text":"{\"source_cache\": \"artifacts/zeaxanthin-research/28852075.abstract.txt\", \"locator\": \"Primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"02ce5ff25dc230c1de6bcb2c4e1e48e1d7f8c218f48e6817d1c697b47b319e7b\", \"start_char\": 0, \"end_char\": 1275, \"text_sha256\": \"02ce5ff25dc230c1de6bcb2c4e1e48e1d7f8c218f48e6817d1c697b47b319e7b\"}","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Microscopy, Raman imaging and molecular dynamics","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"Lutein and zeaxanthin orientation","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Model-bilayer geometry is not a measurement of every human retinal membrane.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Zeaxanthin research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"zeaxanthin","display_name":"Dietary (3R,3-prime-R)-zeaxanthin","entity_type_key":"small_molecule"}},{"dimension":"organism","value_text":"Model membrane","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"The pigment spans the membrane rather than remaining only on its surface.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[zeaxanthin-p28852075] Localization and Orientation of Xanthophylls in a Lipid Bilayer. (2017). https://pubmed.ncbi.nlm.nih.gov/28852075/ DOI: 10.1038/s41598-017-10183-7","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"DMPC giant unilamellar vesicles","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"115545e3-6ebe-5afb-a4fa-55f79966086e","evidence_kind":"source_excerpt","locator":"Lines 314-325","start_line":314,"end_line":325,"excerpt":"### zeaxanthin-membrane-orientation\nZeaxanthin adopted a transmembrane orientation in the DMPC bilayer, with mean tilt near 40 degrees to the membrane normal.\nCondition category: normal\nnutrient_topic: Zeaxanthin research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: The pigment spans the membrane rather than remaining only on its surface.\norganism: Model membrane\ntissue_or_cell_type: DMPC giant unilamellar vesicles\nexperimental_model: Microscopy, Raman imaging and molecular dynamics\nlimitations: Model-bilayer geometry is not a measurement of every human retinal membrane.\nexposure: Lutein and zeaxanthin orientation\nevidence_span: {\"source_cache\": \"artifacts/zeaxanthin-research/28852075.abstract.txt\", \"locator\": \"Primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"02ce5ff25dc230c1de6bcb2c4e1e48e1d7f8c218f48e6817d1c697b47b319e7b\", \"start_char\": 0, \"end_char\": 1275, \"text_sha256\": \"02ce5ff25dc230c1de6bcb2c4e1e48e1d7f8c218f48e6817d1c697b47b319e7b\"}\n[zeaxanthin-p28852075] Localization and Orientation of Xanthophylls in a Lipid Bilayer. 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