{"id":"2f9a96e8-ef16-5123-92de-2eaccd8e4a5b","stable_key":"6cdb37aa-8998-5ea8-829d-4f995caf98fc:l-carnitine-octn2-stereo","predicate":"lower_affinity_than","statement":"Human OCTN2 transported D-carnitine with lower affinity than L-carnitine: reported Km values were 10.9 versus 4.3 micromolar.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"329a4957-79a5-56ad-b84a-c6f94d571cd4","mechanism_event_label":"The two mirror-image molecules are handled differently.","subject":{"id":"34acbb36-cd9d-52bb-af49-4a23f4001813","slug":"d-carnitine","display_name":"D-Carnitine","entity_type_key":"small_molecule"},"object":{"id":"6e34c035-9371-578f-b799-fd2a14e9e40f","slug":"l-carnitine","display_name":"L-Carnitine","entity_type_key":"small_molecule"},"evidence_count":1,"mechanism_event":{"id":"329a4957-79a5-56ad-b84a-c6f94d571cd4","stable_key":"6cdb37aa-8998-5ea8-829d-4f995caf98fc:l-carnitine-octn2-stereo-event","event_type":"observed_relationship","label":"The two mirror-image molecules are handled differently.","description":"Human OCTN2 transported D-carnitine with lower affinity than L-carnitine: reported Km values were 10.9 versus 4.3 micromolar.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"34acbb36-cd9d-52bb-af49-4a23f4001813","slug":"d-carnitine","display_name":"D-Carnitine","entity_type_key":"small_molecule"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"6e34c035-9371-578f-b799-fd2a14e9e40f","slug":"l-carnitine","display_name":"L-Carnitine","entity_type_key":"small_molecule"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"fb9ae9da-e4d3-5557-baac-d8b00e98ba10","slug":"slc22a5","display_name":"Human carnitine transporter OCTN2 / SLC22A5","entity_type_key":"protein"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""}]},"contexts":[{"dimension":"evidence_access","value_text":"Primary abstract","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Transporter expression assay.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"D-carnitine is an experimental comparator, not a substitute.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"L-Carnitine collection; isomer, preparation, species, exposure and manipulation remain explicit.","comparator":null,"unit":null,"notes":"","entity":{"slug":"l-carnitine","display_name":"L-Carnitine","entity_type_key":"small_molecule"}},{"dimension":"plain_language","value_text":"The two mirror-image molecules are handled differently.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"Na(+)-dependent carnitine transport by organic cation transporter (OCTN2): its pharmacological and toxicological relevance. · 1999 · https://pubmed.ncbi.nlm.nih.gov/10525100/","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"a10c22bb-95e7-54d0-a798-7b0e35b77313","evidence_kind":"source_excerpt","locator":"Lines 58-64","start_line":58,"end_line":64,"excerpt":"## l-carnitine-octn2-stereo\nThe two mirror-image molecules are handled differently.\nHuman OCTN2 transported D-carnitine with lower affinity than L-carnitine: reported Km values were 10.9 versus 4.3 micromolar.\nModel: Transporter expression assay.\nLimitations: D-carnitine is an experimental comparator, not a substitute.\nEvidence access: Primary abstract\nNa(+)-dependent carnitine transport by organic cation transporter (OCTN2): its pharmacological and toxicological relevance. · 1999 · https://pubmed.ncbi.nlm.nih.gov/10525100/","model_system":"Transporter expression assay.","directness":"reported_statement","verification_status":"source_derived_draft","notes":"Original curation paraphrase; evidence access and experimental limitations specified.","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"e2c9c42b-806a-55e2-abde-b0320ea94704","stable_key":"import-6cdb37aa-8998-5ea8-829d-4f995caf98fc","title":"L-Carnitine: synthesis, acyl-group transport, fuel selection and nutrient interactions (2026-09-19)","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":"6fcd86d9d02babb48b2ce658d506afe84580ad4b242f93f11f742d934fa5b361","revision_id":"398e3b52-45bc-52e3-891e-656c19ca674f","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}