{"id":"0f830401-7146-539d-8121-d5e8fd612c83","stable_key":"507ed066-fd6d-5722-9223-97b66302e7e3:glycine-serine-required-context","predicate":"cannot_replace_tested","statement":"In the tested cancer cultures, exogenous glycine did not replace serine for nucleotide synthesis and proliferation; glycine restriction or glycine-cleavage depletion did not impede growth.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"4ab41a49-69bd-5786-bdce-b8f5c0de92eb","mechanism_event_label":"The ability to interconvert two amino acids does not make their supplies interchangeable.","subject":{"id":"2b507258-430c-51fe-9fd2-e510c2c197a9","slug":"glycine","display_name":"Glycine","entity_type_key":"small_molecule"},"object":{"id":"c882cd0b-9d83-5b07-bd1c-fe4d45657dcb","slug":"l-serine","display_name":"L-Serine","entity_type_key":"small_molecule"},"evidence_count":1,"mechanism_event":{"id":"4ab41a49-69bd-5786-bdce-b8f5c0de92eb","stable_key":"507ed066-fd6d-5722-9223-97b66302e7e3:glycine-serine-required-context-event","event_type":"observed_relationship","label":"The ability to interconvert two amino acids does not make their supplies interchangeable.","description":"In the tested cancer cultures, exogenous glycine did not replace serine for nucleotide synthesis and proliferation; glycine restriction or glycine-cleavage depletion did not impede growth.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"2b507258-430c-51fe-9fd2-e510c2c197a9","slug":"glycine","display_name":"Glycine","entity_type_key":"small_molecule"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"c882cd0b-9d83-5b07-bd1c-fe4d45657dcb","slug":"l-serine","display_name":"L-Serine","entity_type_key":"small_molecule"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"d2b23343-c688-5fc3-9f42-bfac0050552b","slug":"tetrahydrofolate","display_name":"Tetrahydrofolate","entity_type_key":"small_molecule"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""}]},"contexts":[{"dimension":"evidence_access","value_text":"Primary abstract","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Primary cancer-cell nutrient-restriction and metabolic tracing study.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Abstract-level extraction; model-specific result does not negate glycine-dependent growth in other culture conditions.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Glycine collection; species, compartment, exposure, co-substrates and manipulation remain explicit.","comparator":null,"unit":null,"notes":"","entity":{"slug":"glycine","display_name":"Glycine","entity_type_key":"small_molecule"}},{"dimension":"plain_language","value_text":"The ability to interconvert two amino acids does not make their supplies interchangeable.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"Serine, but not glycine, supports one-carbon metabolism and proliferation of cancer cells. · 2014 · https://pubmed.ncbi.nlm.nih.gov/24813884/ · DOI 10.1016/j.celrep.2014.04.045","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"978b24f4-9183-5d72-bca7-9d6bf6fc5155","evidence_kind":"source_excerpt","locator":"Lines 170-176","start_line":170,"end_line":176,"excerpt":"## glycine-serine-required-context\nThe ability to interconvert two amino acids does not make their supplies interchangeable.\nIn the tested cancer cultures, exogenous glycine did not replace serine for nucleotide synthesis and proliferation; glycine restriction or glycine-cleavage depletion did not impede growth.\nModel: Primary cancer-cell nutrient-restriction and metabolic tracing study.\nLimitations: Abstract-level extraction; model-specific result does not negate glycine-dependent growth in other culture conditions.\nEvidence access: Primary abstract\nSerine, but not glycine, supports one-carbon metabolism and proliferation of cancer cells. · 2014 · https://pubmed.ncbi.nlm.nih.gov/24813884/ · DOI 10.1016/j.celrep.2014.04.045","model_system":"Primary cancer-cell nutrient-restriction and metabolic tracing study.","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":"7b2859d8-e2bf-51e7-8e32-0715c10cbc49","stable_key":"import-507ed066-fd6d-5722-9223-97b66302e7e3","title":"Glycine: supply, one-carbon allocation, receptors 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":"4fabd2fc8e71ca156c91023e7340be3f5a02ae03e91d3a24b231c2adfb0de0aa","revision_id":"24801e49-34a8-53c3-bdf5-b59143441450","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}