{"id":"9bfae962-185d-5285-b815-7901babb0e01","stable_key":"63ce713e-6aea-59f6-9896-ca30e010b2ce:l-tyrosine-bacterial-import","predicate":"when_genes_lost_reduces","statement":"Loss of two C. difficile ABC-transporter genes was associated with lower tyrosine/phenylalanine uptake and p-cresol production, without a measurable growth or enterotoxin effect.","claim_class":"observational","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"076bada6-72b2-5643-8cdc-866750934d02","mechanism_event_label":"Microbial access to a nutrient can change its products without stopping growth.","subject":{"id":"719f63ff-df57-52f9-9f4d-a09fc80b9c22","slug":"c-difficile-aromatic-abc-transporter","display_name":"Clostridioides difficile aromatic amino-acid ABC transport system","entity_type_key":"cellular_process"},"object":{"id":"0acfd2eb-4ac3-5045-add8-614757981f1f","slug":"c-difficile-tyrosine-fermentation","display_name":"Clostridioides difficile tyrosine fermentation","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"076bada6-72b2-5643-8cdc-866750934d02","stable_key":"63ce713e-6aea-59f6-9896-ca30e010b2ce:l-tyrosine-bacterial-import-event","event_type":"observed_relationship","label":"Microbial access to a nutrient can change its products without stopping growth.","description":"Loss of two C. difficile ABC-transporter genes was associated with lower tyrosine/phenylalanine uptake and p-cresol production, without a measurable growth or enterotoxin effect.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"719f63ff-df57-52f9-9f4d-a09fc80b9c22","slug":"c-difficile-aromatic-abc-transporter","display_name":"Clostridioides difficile aromatic amino-acid ABC transport system","entity_type_key":"cellular_process"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"0acfd2eb-4ac3-5045-add8-614757981f1f","slug":"c-difficile-tyrosine-fermentation","display_name":"Clostridioides difficile tyrosine fermentation","entity_type_key":"cellular_process"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"bcfef85f-831d-5439-ba51-1aef4b090441","slug":"l-tyrosine","display_name":"L-Tyrosine","entity_type_key":"small_molecule"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"190407ad-0219-54b5-b05f-7c75f3895ca6","slug":"l-phenylalanine","display_name":"L-Phenylalanine","entity_type_key":"small_molecule"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""},{"entity":{"id":"f08177fb-b34e-5589-a96c-46066ef57131","slug":"p-cresol","display_name":"Para-cresol / p-cresol","entity_type_key":"small_molecule"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":4,"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":"Genomic and phenotypic strain comparisons; convergent loss and laboratory emergence.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Association is retained as such; this is not direct human host transporter evidence.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"L-Tyrosine collection; species, compartment, exposure, co-substrates and manipulation remain explicit.","comparator":null,"unit":null,"notes":"","entity":{"slug":"l-tyrosine","display_name":"L-Tyrosine","entity_type_key":"small_molecule"}},{"dimension":"plain_language","value_text":"Microbial access to a nutrient can change its products without stopping growth.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"Convergent Loss of ABC Transporter Genes From Clostridioides difficile Genomes Is Associated With Impaired Tyrosine Uptake and p-Cresol Production. · 2018 · https://pubmed.ncbi.nlm.nih.gov/29867812/ · DOI 10.3389/fmicb.2018.00901","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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