{"id":"c5a1837a-1b46-5b46-88d0-11ca1d409c83","stable_key":"649e861b-265a-5912-bc36-3a73e53ef892:l-serine-psph-feedback","predicate":"inhibits_isolated","statement":"Serine inhibited isolated PSPH, but this inhibition did not control flux through the reconstructed phosphorylated pathway unless PSPH activity was severely impaired.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"d9289d3b-eeaf-523a-828e-b5d2c1eb7091","mechanism_event_label":"Feedback measured on one enzyme need not control the whole pathway.","subject":{"id":"c882cd0b-9d83-5b07-bd1c-fe4d45657dcb","slug":"l-serine","display_name":"L-Serine","entity_type_key":"small_molecule"},"object":{"id":"1177919d-d7f4-5272-b40c-444f5dbee4d2","slug":"psph","display_name":"Human phosphoserine phosphatase / PSPH","entity_type_key":"protein"},"evidence_count":1,"mechanism_event":{"id":"d9289d3b-eeaf-523a-828e-b5d2c1eb7091","stable_key":"649e861b-265a-5912-bc36-3a73e53ef892:l-serine-psph-feedback-event","event_type":"observed_relationship","label":"Feedback measured on one enzyme need not control the whole pathway.","description":"Serine inhibited isolated PSPH, but this inhibition did not control flux through the reconstructed phosphorylated pathway unless PSPH activity was severely impaired.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"c882cd0b-9d83-5b07-bd1c-fe4d45657dcb","slug":"l-serine","display_name":"L-Serine","entity_type_key":"small_molecule"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"1177919d-d7f4-5272-b40c-444f5dbee4d2","slug":"psph","display_name":"Human phosphoserine phosphatase / PSPH","entity_type_key":"protein"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""}]},"contexts":[{"dimension":"evidence_access","value_text":"Primary abstract","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Human enzyme assays and pathway-flux analysis.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Pathway reconstruction is not a measurement of all tissues in vivo.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"L-Serine collection; species, compartment, exposure, co-substrates and manipulation remain explicit.","comparator":null,"unit":null,"notes":"","entity":{"slug":"l-serine","display_name":"L-Serine","entity_type_key":"small_molecule"}},{"dimension":"plain_language","value_text":"Feedback measured on one enzyme need not control the whole pathway.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"Effect of l-serine and magnesium ions on the functional properties of human phosphoserine phosphatase and its pathogenetic variants. · 2024 · https://pubmed.ncbi.nlm.nih.gov/38278334/ · DOI 10.1016/j.bbadis.2024.167034","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"59e89882-4e82-5761-a5ad-a4f0ed41f4eb","evidence_kind":"source_excerpt","locator":"Lines 70-76","start_line":70,"end_line":76,"excerpt":"## l-serine-psph-feedback\nFeedback measured on one enzyme need not control the whole pathway.\nSerine inhibited isolated PSPH, but this inhibition did not control flux through the reconstructed phosphorylated pathway unless PSPH activity was severely impaired.\nModel: Human enzyme assays and pathway-flux analysis.\nLimitations: Pathway reconstruction is not a measurement of all tissues in vivo.\nEvidence access: Primary abstract\nEffect of l-serine and magnesium ions on the functional properties of human phosphoserine phosphatase and its pathogenetic variants. · 2024 · https://pubmed.ncbi.nlm.nih.gov/38278334/ · DOI 10.1016/j.bbadis.2024.167034","model_system":"Human enzyme assays and pathway-flux analysis.","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":"70bcf57a-36bb-563f-9073-2d616e5f155a","stable_key":"import-649e861b-265a-5912-bc36-3a73e53ef892","title":"L-Serine: synthesis, one-carbon metabolism, lipids 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":"22a750ce2b94f8607268c58322c48c4f0468f403b72a4008307538a6e5ff86d5","revision_id":"c1d6a7e1-9558-5bc6-9e3b-7080c26d3dbc","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}