{"id":"b553f384-9264-558f-8a9c-7c78ff68e063","stable_key":"649e861b-265a-5912-bc36-3a73e53ef892:l-serine-srr-racemization","predicate":"racemizes_l_serine_to","statement":"Human serine racemase catalyzes the PLP-dependent formation of D-serine from L-serine; replacing Ser84 with alanine shifted its behavior toward serine dehydratase activity.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"adb1b85a-f3d7-5d88-8cc5-ffae5f1db374","mechanism_event_label":"One enzyme creates the D-form used in a distinct signaling pathway.","subject":{"id":"3ea2d19a-b88a-531e-9cd3-a993735143de","slug":"srr","display_name":"Human serine racemase / SRR","entity_type_key":"protein"},"object":{"id":"7f3bf9f5-b1b1-5381-baa6-72800ceb5436","slug":"d-serine","display_name":"D-Serine","entity_type_key":"small_molecule"},"evidence_count":1,"mechanism_event":{"id":"adb1b85a-f3d7-5d88-8cc5-ffae5f1db374","stable_key":"649e861b-265a-5912-bc36-3a73e53ef892:l-serine-srr-racemization-event","event_type":"observed_relationship","label":"One enzyme creates the D-form used in a distinct signaling pathway.","description":"Human serine racemase catalyzes the PLP-dependent formation of D-serine from L-serine; replacing Ser84 with alanine shifted its behavior toward serine dehydratase activity.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"3ea2d19a-b88a-531e-9cd3-a993735143de","slug":"srr","display_name":"Human serine racemase / SRR","entity_type_key":"protein"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"7f3bf9f5-b1b1-5381-baa6-72800ceb5436","slug":"d-serine","display_name":"D-Serine","entity_type_key":"small_molecule"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"c882cd0b-9d83-5b07-bd1c-fe4d45657dcb","slug":"l-serine","display_name":"L-Serine","entity_type_key":"small_molecule"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"6b656ff5-9532-5da4-8eea-8ca163a48649","slug":"pyridoxal-phosphate","display_name":"PLP","entity_type_key":"small_molecule"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""},{"entity":{"id":"fc4df87c-aec1-5de5-8122-effc2c5ee721","slug":"sds","display_name":"Human hepatic serine dehydratase / SDS","entity_type_key":"protein"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":4,"notes":""}]},"contexts":[{"dimension":"evidence_access","value_text":"Primary abstract","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Recombinant human serine racemase and serine dehydratase mutants with functional comparisons.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Engineered reaction switching does not mean the native enzymes have identical functions.","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":"One enzyme creates the D-form used in a distinct signaling pathway.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"Modulating the function of human serine racemase and human serine dehydratase by protein engineering. · 2012 · https://pubmed.ncbi.nlm.nih.gov/23112234/ · DOI 10.1093/protein/gzs078","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"93529f70-18df-5caa-b14a-d523db77102f","evidence_kind":"source_excerpt","locator":"Lines 406-412","start_line":406,"end_line":412,"excerpt":"## l-serine-srr-racemization\nOne enzyme creates the D-form used in a distinct signaling pathway.\nHuman serine racemase catalyzes the PLP-dependent formation of D-serine from L-serine; replacing Ser84 with alanine shifted its behavior toward serine dehydratase activity.\nModel: Recombinant human serine racemase and serine dehydratase mutants with functional comparisons.\nLimitations: Engineered reaction switching does not mean the native enzymes have identical functions.\nEvidence access: Primary abstract\nModulating the function of human serine racemase and human serine dehydratase by protein engineering. · 2012 · https://pubmed.ncbi.nlm.nih.gov/23112234/ · DOI 10.1093/protein/gzs078","model_system":"Recombinant human serine racemase and serine dehydratase mutants with functional comparisons.","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}