{"id":"b68ac609-d4db-5aad-a297-4fd1caeb63f0","stable_key":"59b18080-c560-563d-abc5-bac4ee82a27c:ergothioneine-egta-precursor","predicate":"produces","statement":"The described Mycobacterium smegmatis pathway uses EgtA to condense glutamate and cysteine into gamma-glutamylcysteine.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"649aa533-8141-5cf1-a6e9-550d8b92bde8","mechanism_event_label":"A separately encoded enzyme prepares the sulfur donor.","subject":{"id":"a7bfd84a-f293-5cd7-b403-df29d74b23e6","slug":"mycobacterium-smegmatis-egta","display_name":"Mycobacterium smegmatis EgtA","entity_type_key":"protein"},"object":{"id":"d47d2006-2fb8-56ea-a76a-7919171f66ce","slug":"gamma-glutamylcysteine","display_name":"Gamma-glutamylcysteine","entity_type_key":"small_molecule"},"evidence_count":1,"mechanism_event":{"id":"649aa533-8141-5cf1-a6e9-550d8b92bde8","stable_key":"59b18080-c560-563d-abc5-bac4ee82a27c:ergothioneine-egta-precursor-event","event_type":"observed_relationship","label":"A separately encoded enzyme prepares the sulfur donor.","description":"The described Mycobacterium smegmatis pathway uses EgtA to condense glutamate and cysteine into gamma-glutamylcysteine.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"a7bfd84a-f293-5cd7-b403-df29d74b23e6","slug":"mycobacterium-smegmatis-egta","display_name":"Mycobacterium smegmatis EgtA","entity_type_key":"protein"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"d47d2006-2fb8-56ea-a76a-7919171f66ce","slug":"gamma-glutamylcysteine","display_name":"Gamma-glutamylcysteine","entity_type_key":"small_molecule"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"939c92c3-50ea-5a4a-9654-8e3b94448132","slug":"ergothioneine","display_name":"L-Ergothioneine","entity_type_key":"small_molecule"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"7da684a4-2641-5bc6-93ae-8c6aa384e487","slug":"glutamate","display_name":"L-Glutamate","entity_type_key":"small_molecule"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""},{"entity":{"id":"ca899f13-50ad-55e5-ab99-329ae0038c74","slug":"l-cysteine","display_name":"L-Cysteine","entity_type_key":"small_molecule"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":4,"notes":""}]},"contexts":[{"dimension":"evidence_access","value_text":"Primary full text, pathway background citing original reconstitution","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Pathway description in the primary EgtE paper, citing the original reconstitution.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"This step is cited background, not a new EgtA experiment in this paper; microbial and human pathways remain separate.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Ergothioneine collection; molecular form, preparation, species, exposure and manipulation remain explicit.","comparator":null,"unit":null,"notes":"","entity":{"slug":"ergothioneine","display_name":"L-Ergothioneine","entity_type_key":"small_molecule"}},{"dimension":"plain_language","value_text":"A separately encoded enzyme prepares the sulfur donor.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"Mechanistic studies of a novel C-S lyase in ergothioneine biosynthesis: the involvement of a sulfenic acid intermediate. · 2015 · https://pubmed.ncbi.nlm.nih.gov/26149121/ · DOI 10.1038/srep11870","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"593e3782-6dcc-5a9f-ade1-d778461297e2","evidence_kind":"source_excerpt","locator":"Lines 560-566","start_line":560,"end_line":566,"excerpt":"## ergothioneine-egta-precursor\nA separately encoded enzyme prepares the sulfur donor.\nThe described Mycobacterium smegmatis pathway uses EgtA to condense glutamate and cysteine into gamma-glutamylcysteine.\nModel: Pathway description in the primary EgtE paper, citing the original reconstitution.\nLimitations: This step is cited background, not a new EgtA experiment in this paper; microbial and human pathways remain separate.\nEvidence access: Primary full text, pathway background citing original reconstitution\nMechanistic studies of a novel C-S lyase in ergothioneine biosynthesis: the involvement of a sulfenic acid intermediate. · 2015 · https://pubmed.ncbi.nlm.nih.gov/26149121/ · DOI 10.1038/srep11870","model_system":"Pathway description in the primary EgtE paper, citing the original reconstitution.","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":"2f037d98-f3d0-5dbe-80d8-90b738f130d6","stable_key":"import-59b18080-c560-563d-abc5-bac4ee82a27c","title":"Ergothioneine: transport, redox chemistry and cross-nutrient mechanisms (2026-09-19)","document_type":"imported_text","citation_label":"AI-assisted research curation; primary references, access levels and experimental limitations individually identified. Not publisher full text.","file_path":"","sha256":"b6def8119f03cfabeec2fb55ba924340dc612e1dd42f05404201fa2b7ced5259","revision_id":"f88c38e6-ffb5-5a68-83ca-4610ca2c2df4","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}