{"id":"138cf9c9-9df4-598f-a461-37bd4357cb47","stable_key":"97957230-601f-5dec-8524-0812be8fadbf:l-threonine-microbial-ketoacid","predicate":"converts_ketoacid_to","statement":"E. coli mutant and enzyme studies showed TdcE conversion of threonine-derived 2-ketobutyrate into propionyl-CoA during anaerobic growth.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"b591f9d9-9eb7-50f4-a640-2f6415bdadb2","mechanism_event_label":"Microbes have a separate route for fermenting threonine carbon.","subject":{"id":"0a29de13-4ddb-5617-956c-910d8291052f","slug":"e-coli-tdce","display_name":"Escherichia coli 2-ketobutyrate formate-lyase / TdcE","entity_type_key":"protein"},"object":{"id":"69ac0570-94d8-59d8-85ef-7f67cf302d16","slug":"propionyl-coa","display_name":"Propionyl-CoA","entity_type_key":"small_molecule"},"evidence_count":1,"mechanism_event":{"id":"b591f9d9-9eb7-50f4-a640-2f6415bdadb2","stable_key":"97957230-601f-5dec-8524-0812be8fadbf:l-threonine-microbial-ketoacid-event","event_type":"observed_relationship","label":"Microbes have a separate route for fermenting threonine carbon.","description":"E. coli mutant and enzyme studies showed TdcE conversion of threonine-derived 2-ketobutyrate into propionyl-CoA during anaerobic growth.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"0a29de13-4ddb-5617-956c-910d8291052f","slug":"e-coli-tdce","display_name":"Escherichia coli 2-ketobutyrate formate-lyase / TdcE","entity_type_key":"protein"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"69ac0570-94d8-59d8-85ef-7f67cf302d16","slug":"propionyl-coa","display_name":"Propionyl-CoA","entity_type_key":"small_molecule"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"fcef4dc2-a7b6-5812-bc33-c8af3d83f4d0","slug":"l-threonine","display_name":"L-Threonine","entity_type_key":"small_molecule"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"dee03e61-050d-5bde-ad0a-7f9652799ec8","slug":"alpha-ketobutyrate","display_name":"Alpha-ketobutyrate","entity_type_key":"small_molecule"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""}]},"contexts":[{"dimension":"evidence_access","value_text":"Primary abstract","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"E. coli operon analysis, mutants, enzyme assays and culture-supernatant NMR.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"This is not a human enzyme reaction or a measurement of net propionate production in the human gut.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"L-Threonine collection; species, compartment, exposure, co-substrates and manipulation remain explicit.","comparator":null,"unit":null,"notes":"","entity":{"slug":"l-threonine","display_name":"L-Threonine","entity_type_key":"small_molecule"}},{"dimension":"plain_language","value_text":"Microbes have a separate route for fermenting threonine carbon.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"Novel keto acid formate-lyase and propionate kinase enzymes are components of an anaerobic pathway in Escherichia coli that degrades L-threonine to propionate. · 1998 · https://pubmed.ncbi.nlm.nih.gov/9484901/ · DOI 10.1046/j.1365-2958.1998.00696.x","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"f63f16e0-24dc-556f-93a8-e1d5c7bab4e9","evidence_kind":"source_excerpt","locator":"Lines 426-432","start_line":426,"end_line":432,"excerpt":"## l-threonine-microbial-ketoacid\nMicrobes have a separate route for fermenting threonine carbon.\nE. coli mutant and enzyme studies showed TdcE conversion of threonine-derived 2-ketobutyrate into propionyl-CoA during anaerobic growth.\nModel: E. coli operon analysis, mutants, enzyme assays and culture-supernatant NMR.\nLimitations: This is not a human enzyme reaction or a measurement of net propionate production in the human gut.\nEvidence access: Primary abstract\nNovel keto acid formate-lyase and propionate kinase enzymes are components of an anaerobic pathway in Escherichia coli that degrades L-threonine to propionate. · 1998 · https://pubmed.ncbi.nlm.nih.gov/9484901/ · DOI 10.1046/j.1365-2958.1998.00696.x","model_system":"E. coli operon analysis, mutants, enzyme assays and culture-supernatant NMR.","directness":"reported_statement","verification_status":"source_derived_draft","notes":"Original curation paraphrase; 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Not publisher full text.","file_path":"","sha256":"3365aed939d9f567bd098449c7d67c7c00fb6c9ba163dcf34dc7cf6081f324fb","revision_id":"10a7b648-8dd7-5d4e-b618-c560a6e2d3c7","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}