{"id":"d1d1b701-f65d-5cc7-a584-ec314c9589a6","stable_key":"a9dd23c6-978a-5755-8bd8-f29bd1fe0cda:b3-cons-sarm-e642a-loss","predicate":"fails_to_hydrolyze","statement":"The human SARM1 TIR E642A mutant failed to cleave NAD+ in the cell-free NADase assay.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"negative","is_public":true,"mechanism_event_id":"e50258a9-1e22-5c41-a64e-e06a409960f4","mechanism_event_label":"Changing a catalytic glutamate disabled NAD cleavage in the assay.","subject":{"id":"9f112f24-3aa4-5624-a691-a491dfa89c8a","slug":"sarm1-tir-e642a","display_name":"Human SARM1 TIR E642A construct","entity_type_key":"protein_state"},"object":{"id":"283ed24b-06a1-50aa-9281-df3bac6ce37e","slug":"nad-plus","display_name":"NAD+","entity_type_key":"small_molecule"},"evidence_count":1,"mechanism_event":{"id":"e50258a9-1e22-5c41-a64e-e06a409960f4","stable_key":"a9dd23c6-978a-5755-8bd8-f29bd1fe0cda:b3-cons-sarm-e642a-loss-event","event_type":"biochemical_relationship","label":"Changing a catalytic glutamate disabled NAD cleavage in the assay.","description":"The human SARM1 TIR E642A mutant failed to cleave NAD+ in the cell-free NADase assay.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"9f112f24-3aa4-5624-a691-a491dfa89c8a","slug":"sarm1-tir-e642a","display_name":"Human SARM1 TIR E642A construct","entity_type_key":"protein_state"},"role":"impaired_enzyme","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"283ed24b-06a1-50aa-9281-df3bac6ce37e","slug":"nad-plus","display_name":"NAD+","entity_type_key":"small_molecule"},"role":"substrate","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""}]},"contexts":[{"dimension":"availability_state","value_text":"machinery_impairment","comparator":null,"unit":null,"notes":"Imported condition classification; unverified.","entity":null},{"dimension":"cross_nutrient","value_text":"false","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"evidence_span","value_text":"{\"source_cache\": \"artifacts/niacin-consumption-sources/sarm2017.txt\", \"locator\": \"Full text, normalized paragraph 27\", \"start_char\": 18354, \"end_char\": 20343, \"file_sha256\": \"fc30de231911f5c30425173d684495e62c725ba27c78d44592e6bc68433ef545\", \"text_sha256\": \"eda6dc283d30b48f68dc8626f2ea00ffb36d08cf8597eb6e7b1ce7e091fd0cb3\"}","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Cell-free translation, purification and NADase assay","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"E642A compared with wild-type TIR","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Purified engineered TIR fragment rather than basal activity of intact full-length SARM1; no dietary dose inference.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Niacin research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"niacin","display_name":"Niacin (vitamin B3)","entity_type_key":"nutrient_element"}},{"dimension":"organism","value_text":"Human","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"Changing a catalytic glutamate disabled NAD cleavage in the assay.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[b3-cons-sarm2017] The SARM1 Toll/Interleukin-1 Receptor Domain Possesses Intrinsic NAD+ Cleavage Activity that Promotes Pathological Axonal Degeneration. (2017). https://pubmed.ncbi.nlm.nih.gov/28334607/ DOI: 10.1016/j.neuron.2017.02.022","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Purified human mutant domain","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"trigger_kind","value_text":"machinery_impairment","comparator":null,"unit":null,"notes":"Imported condition classification; unverified.","entity":null}],"evidence":[{"id":"e763adf7-3a87-5644-be90-ee41895559e1","evidence_kind":"source_excerpt","locator":"Lines 719-731","start_line":719,"end_line":731,"excerpt":"### b3-cons-sarm-e642a-loss\nThe human SARM1 TIR E642A mutant failed to cleave NAD+ in the cell-free NADase assay.\nCondition category: machinery_impairment\nnutrient_topic: Niacin research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Changing a catalytic glutamate disabled NAD cleavage in the assay.\norganism: Human\ntissue_or_cell_type: Purified human mutant domain\nexperimental_model: Cell-free translation, purification and NADase assay\nlimitations: Purified engineered TIR fragment rather than basal activity of intact full-length SARM1; no dietary dose inference.\nexposure: E642A compared with wild-type TIR\ncross_nutrient: false\nevidence_span: {\"source_cache\": \"artifacts/niacin-consumption-sources/sarm2017.txt\", \"locator\": \"Full text, normalized paragraph 27\", \"start_char\": 18354, \"end_char\": 20343, \"file_sha256\": \"fc30de231911f5c30425173d684495e62c725ba27c78d44592e6bc68433ef545\", \"text_sha256\": \"eda6dc283d30b48f68dc8626f2ea00ffb36d08cf8597eb6e7b1ce7e091fd0cb3\"}\n[b3-cons-sarm2017] The SARM1 Toll/Interleukin-1 Receptor Domain Possesses Intrinsic NAD+ Cleavage Activity that Promotes Pathological Axonal Degeneration. 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