{"id":"2ce93509-c555-5e46-801f-16d964bd0d12","stable_key":"41a89233-da9a-5b7b-9c18-e19bbadcfe2d:methionine-apip-salvage","predicate":"supports","statement":"APIP depletion impaired HeLa growth when methionine was replaced by MTA, supporting its role in the salvage pathway.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"24a9bc40-e159-5085-885a-efcd87dec1dc","mechanism_event_label":"Recycling sulfur back to methionine needs additional enzymes beyond MTAP.","subject":{"id":"d4e3b8c8-690d-58ba-8a00-99221988daf8","slug":"apip","display_name":"Human methylthioribulose-1-phosphate dehydratase / APIP","entity_type_key":"protein"},"object":{"id":"43e23920-7bc7-5b69-9ffd-6528b5be4ece","slug":"human-mta-supported-growth","display_name":"Growth of human cells supplied MTA instead of methionine","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"24a9bc40-e159-5085-885a-efcd87dec1dc","stable_key":"41a89233-da9a-5b7b-9c18-e19bbadcfe2d:methionine-apip-salvage-event","event_type":"observed_relationship","label":"Recycling sulfur back to methionine needs additional enzymes beyond MTAP.","description":"APIP depletion impaired HeLa growth when methionine was replaced by MTA, supporting its role in the salvage pathway.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"d4e3b8c8-690d-58ba-8a00-99221988daf8","slug":"apip","display_name":"Human methylthioribulose-1-phosphate dehydratase / APIP","entity_type_key":"protein"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"43e23920-7bc7-5b69-9ffd-6528b5be4ece","slug":"human-mta-supported-growth","display_name":"Growth of human cells supplied MTA instead of methionine","entity_type_key":"cellular_process"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"9d39f561-740b-5f67-bba7-8a72ef612a99","slug":"methionine","display_name":"L-Methionine","entity_type_key":"small_molecule"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"525860da-a986-5d19-97f0-a257a454b649","slug":"5-methylthioadenosine","display_name":"5′-Methylthioadenosine","entity_type_key":"small_molecule"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""}]},"contexts":[{"dimension":"availability_state","value_text":"machinery_impairment","comparator":null,"unit":null,"notes":"Imported condition classification; unverified.","entity":null},{"dimension":"evidence_access","value_text":"Primary abstract","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Human HeLa knockdown with supporting microbial reporter assays.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Alternative-substrate culture does not establish the fraction of dietary requirements normally met by salvage.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"L-Methionine collection; species, compartment, exposure, co-substrates and manipulation remain explicit.","comparator":null,"unit":null,"notes":"","entity":{"slug":"methionine","display_name":"L-Methionine","entity_type_key":"small_molecule"}},{"dimension":"plain_language","value_text":"Recycling sulfur back to methionine needs additional enzymes beyond MTAP.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"Functional identification of APIP as human mtnB, a key enzyme in the methionine salvage pathway. · 2012 · https://pubmed.ncbi.nlm.nih.gov/23285211/ · DOI 10.1371/journal.pone.0052877","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"trigger_kind","value_text":"machinery_impairment","comparator":null,"unit":null,"notes":"Imported condition classification; 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