{"id":"b349e39a-f716-545a-802c-ca794d92ae11","stable_key":"a9828b14-fbd7-57bf-9e01-0d52d1b42a1f:citrulline-nos-citrulline","predicate":"produces","statement":"Purified human eNOS converted arginine in an assay measuring citrulline formation, with an arginine Km of 3.9 micromolar.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"d0cfeb5b-64a4-5216-83e1-c83433e46565","mechanism_event_label":"Citrulline is also produced when the nitric-oxide pathway uses arginine.","subject":{"id":"8a9c57f6-eafd-5243-afaf-d4e830939c4b","slug":"nos3","display_name":"Human endothelial nitric oxide synthase / eNOS / NOS3","entity_type_key":"protein"},"object":{"id":"f53c7bfb-3b91-56fe-bebd-28623cfe13a0","slug":"citrulline","display_name":"L-Citrulline","entity_type_key":"small_molecule"},"evidence_count":1,"mechanism_event":{"id":"d0cfeb5b-64a4-5216-83e1-c83433e46565","stable_key":"a9828b14-fbd7-57bf-9e01-0d52d1b42a1f:citrulline-nos-citrulline-event","event_type":"biochemical_relationship","label":"Citrulline is also produced when the nitric-oxide pathway uses arginine.","description":"Purified human eNOS converted arginine in an assay measuring citrulline formation, with an arginine Km of 3.9 micromolar.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"eeca3c9e-7749-5677-b7bd-37fe8f7c228d","slug":"arginine","display_name":"L-Arginine","entity_type_key":"small_molecule"},"role":"substrate","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"8a9c57f6-eafd-5243-afaf-d4e830939c4b","slug":"nos3","display_name":"Human endothelial nitric oxide synthase / eNOS / NOS3","entity_type_key":"protein"},"role":"enzyme","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"f53c7bfb-3b91-56fe-bebd-28623cfe13a0","slug":"citrulline","display_name":"L-Citrulline","entity_type_key":"small_molecule"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""}]},"contexts":[{"dimension":"evidence_span","value_text":"{\"source_cache\": \"artifacts/citrulline-research/10608822.abstract.txt\", \"locator\": \"Primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"1600b193cc63f30b204285729710bb81f34bc2918a8ca7f97aa97bc4acd998fd\", \"start_char\": 0, \"end_char\": 2100, \"text_sha256\": \"1600b193cc63f30b204285729710bb81f34bc2918a8ca7f97aa97bc4acd998fd\"}","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Purified recombinant enzyme activity and cofactor analysis","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"Arginine substrate; BH4, FAD, FMN, heme, iron and zinc measurements","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Biochemical cofactor findings do not show that extra dietary cofactors increase NO in healthy people.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Citrulline research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"citrulline","display_name":"L-Citrulline","entity_type_key":"small_molecule"}},{"dimension":"organism","value_text":"Human NOS3 expressed in yeast","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"Citrulline is also produced when the nitric-oxide pathway uses arginine.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[citrulline-p10608822] Characterization of recombinant human endothelial nitric-oxide synthase purified from the yeast Pichia pastoris. (1999). https://pubmed.ncbi.nlm.nih.gov/10608822/ DOI: 10.1074/jbc.274.53.37658","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Endothelial NOS enzyme preparation","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"e08cb3b7-fd9c-530d-abb2-3d3816cc5af0","evidence_kind":"source_excerpt","locator":"Lines 502-513","start_line":502,"end_line":513,"excerpt":"### citrulline-nos-citrulline\nPurified human eNOS converted arginine in an assay measuring citrulline formation, with an arginine Km of 3.9 micromolar.\nCondition category: normal\nnutrient_topic: Citrulline research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Citrulline is also produced when the nitric-oxide pathway uses arginine.\norganism: Human NOS3 expressed in yeast\ntissue_or_cell_type: Endothelial NOS enzyme preparation\nexperimental_model: Purified recombinant enzyme activity and cofactor analysis\nlimitations: Biochemical cofactor findings do not show that extra dietary cofactors increase NO in healthy people.\nexposure: Arginine substrate; BH4, FAD, FMN, heme, iron and zinc measurements\nevidence_span: {\"source_cache\": \"artifacts/citrulline-research/10608822.abstract.txt\", \"locator\": \"Primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"1600b193cc63f30b204285729710bb81f34bc2918a8ca7f97aa97bc4acd998fd\", \"start_char\": 0, \"end_char\": 2100, \"text_sha256\": \"1600b193cc63f30b204285729710bb81f34bc2918a8ca7f97aa97bc4acd998fd\"}\n[citrulline-p10608822] Characterization of recombinant human endothelial nitric-oxide synthase purified from the yeast Pichia pastoris. 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