{"id":"cdb6a10c-80a2-5ec4-9297-b41a71b8de82","stable_key":"c3df3634-4c3a-5099-a5d9-e4f6344c1084:crym-p2c-reduction","predicate":"converted_to","statement":"CRYM ketimine reductase reduces P2C to L-pipecolate using reduced nicotinamide cofactors.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"776b03bb-4054-59d2-9edc-a812471b580b","mechanism_event_label":"A ring-shaped intermediate can be reduced to pipecolate.","subject":{"id":"53682952-99a5-5e00-a34a-54ed265b9134","slug":"piperideine-2-carboxylate","display_name":"Delta1-piperideine-2-carboxylate","entity_type_key":"small_molecule"},"object":{"id":"788366f7-4a9d-51e7-adbd-0a87afe092c0","slug":"pipecolate","display_name":"L-Pipecolate","entity_type_key":"small_molecule"},"evidence_count":1,"mechanism_event":{"id":"776b03bb-4054-59d2-9edc-a812471b580b","stable_key":"c3df3634-4c3a-5099-a5d9-e4f6344c1084:crym-p2c-reduction-event","event_type":"biochemical_relationship","label":"A ring-shaped intermediate can be reduced to pipecolate.","description":"CRYM ketimine reductase reduces P2C to L-pipecolate using reduced nicotinamide cofactors.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"393d2192-4809-54d7-a96d-c8a61bca9d4b","slug":"crym","display_name":"mu-Crystallin / CRYM","entity_type_key":"protein"},"role":"catalyst","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"53682952-99a5-5e00-a34a-54ed265b9134","slug":"piperideine-2-carboxylate","display_name":"Delta1-piperideine-2-carboxylate","entity_type_key":"small_molecule"},"role":"substrate","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"4aba2a5e-8d06-5304-bb01-c0402b225a94","slug":"nadph","display_name":"NADPH","entity_type_key":"small_molecule"},"role":"reducing_cofactor","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"be6e4670-953f-5a4e-97da-1e536a54e0e4","slug":"nadp-plus","display_name":"NADP+","entity_type_key":"small_molecule"},"role":"product","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""},{"entity":{"id":"788366f7-4a9d-51e7-adbd-0a87afe092c0","slug":"pipecolate","display_name":"L-Pipecolate","entity_type_key":"small_molecule"},"role":"product","stoichiometry":null,"state_label":"","sequence_order":4,"notes":""}]},"contexts":[{"dimension":"experimental_model","value_text":"Recombinant human CRYM and mammalian enzyme substrate assays","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Catalytic capacity does not determine the route's quantitative contribution to human brain lysine clearance.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"organism","value_text":"Homo sapiens enzyme; ovine enzyme used for initial purification","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"A ring-shaped intermediate can be reduced to pipecolate.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[hallen2011] Mammalian forebrain ketimine reductase identified as mu-crystallin; potential regulation by thyroid hormones. (2011). https://pubmed.ncbi.nlm.nih.gov/21332720/ DOI: 10.1111/j.1471-4159.2011.07220.x\n[hallen2015] Insights into Enzyme Catalysis and Thyroid Hormone Regulation of Cerebral Ketimine Reductase/mu-Crystallin Under Physiological Conditions. (2015). https://pubmed.ncbi.nlm.nih.gov/25931162/ DOI: 10.1007/s11064-015-1590-5","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Cytosolic enzyme; forebrain biochemical context","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"4154d5ca-375c-59d9-9d9a-ee47fe7b9bb1","evidence_kind":"source_excerpt","locator":"Lines 336-345","start_line":336,"end_line":345,"excerpt":"### crym-p2c-reduction\nCRYM ketimine reductase reduces P2C to L-pipecolate using reduced nicotinamide cofactors.\nPlain language: A ring-shaped intermediate can be reduced to pipecolate.\nCondition category: normal\norganism: Homo sapiens enzyme; ovine enzyme used for initial purification\ntissue_or_cell_type: Cytosolic enzyme; forebrain biochemical context\nexperimental_model: Recombinant human CRYM and mammalian enzyme substrate assays\nlimitations: Catalytic capacity does not determine the route's quantitative contribution to human brain lysine clearance.\n[hallen2011] Mammalian forebrain ketimine reductase identified as mu-crystallin; potential regulation by thyroid hormones. (2011). https://pubmed.ncbi.nlm.nih.gov/21332720/ DOI: 10.1111/j.1471-4159.2011.07220.x\n[hallen2015] Insights into Enzyme Catalysis and Thyroid Hormone Regulation of Cerebral Ketimine Reductase/mu-Crystallin Under Physiological Conditions. (2015). https://pubmed.ncbi.nlm.nih.gov/25931162/ DOI: 10.1007/s11064-015-1590-5","model_system":"Recombinant human CRYM and mammalian enzyme substrate assays","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact quote from the accompanying curation document, not from publisher text. Original study references: [hallen2011] Mammalian forebrain ketimine reductase identified as mu-crystallin; potential regulation by thyroid hormones. (2011). https://pubmed.ncbi.nlm.nih.gov/21332720/ DOI: 10.1111/j.1471-4159.2011.07220.x; [hallen2015] Insights into Enzyme Catalysis and Thyroid Hormone Regulation of Cerebral Ketimine Reductase/mu-Crystallin Under Physiological Conditions. (2015). https://pubmed.ncbi.nlm.nih.gov/25931162/ DOI: 10.1007/s11064-015-1590-5","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"7633bde7-dcc9-5086-91c6-a45eb96857f3","stable_key":"import-c3df3634-4c3a-5099-a5d9-e4f6344c1084","title":"L-Lysine: mechanism-first literature curation (2026-09-17)","document_type":"imported_text","citation_label":"AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text.","file_path":"","sha256":"93998d47c21525409ba82f1c82ededf2893dff15fbe61c7deffc175b0e298e97","revision_id":"3897e31f-6624-59e1-a053-8a81b7361632","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}