{"id":"787891d0-e4ac-5079-8040-1b453fd0efdc","stable_key":"ec174d5a-4903-5745-8646-df0e9d4265e8:folate-fpgs-dhf-substrate","predicate":"polyglutamylates","statement":"Dihydrofolate was also an effective substrate for purified human cytosolic FPGS.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"positive","is_public":true,"mechanism_event_id":"b2e95d01-adbf-5f84-b1ab-eed79e323f94","mechanism_event_label":"Polyglutamate tails can be attached before DHF is reduced.","subject":{"id":"ef23c0b4-93bc-5f74-9889-cb7e573568a6","slug":"fpgs-cytosolic","display_name":"Human cytosolic FPGS isoform","entity_type_key":"protein"},"object":{"id":"b6feb26d-6f4d-5232-b54a-650e125fcdf8","slug":"dihydrofolate","display_name":"7,8-Dihydrofolate","entity_type_key":"small_molecule"},"evidence_count":1,"mechanism_event":{"id":"b2e95d01-adbf-5f84-b1ab-eed79e323f94","stable_key":"ec174d5a-4903-5745-8646-df0e9d4265e8:folate-fpgs-dhf-substrate-event","event_type":"biochemical_relationship","label":"Polyglutamate tails can be attached before DHF is reduced.","description":"Dihydrofolate was also an effective substrate for purified human cytosolic FPGS.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"ef23c0b4-93bc-5f74-9889-cb7e573568a6","slug":"fpgs-cytosolic","display_name":"Human cytosolic FPGS isoform","entity_type_key":"protein"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"b6feb26d-6f4d-5232-b54a-650e125fcdf8","slug":"dihydrofolate","display_name":"7,8-Dihydrofolate","entity_type_key":"small_molecule"},"role":"object","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"7da684a4-2641-5bc6-93ae-8c6aa384e487","slug":"glutamate","display_name":"L-Glutamate","entity_type_key":"small_molecule"},"role":"added substrate","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"81c45abb-713d-521f-9854-23288f880831","slug":"folate-polyglutamates","display_name":"Folate polyglutamates","entity_type_key":"chemical_species"},"role":"product","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""}]},"contexts":[{"dimension":"experimental_model","value_text":"Purified human cytosolic FPGS expressed in bacteria","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"Comparative substrate enzyme assays","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Does not establish net DHF pool size in human tissues.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Folate and folic acid research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"folate","display_name":"Folate (vitamin B9)","entity_type_key":"chemical_species"}},{"dimension":"organism","value_text":"Homo sapiens protein expressed in Escherichia coli","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"Polyglutamate tails can be attached before DHF is reduced.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[chen1996] Purification and properties of human cytosolic folylpoly-gamma-glutamate synthetase and organization, localization, and differential splicing of its gene (1996). https://pubmed.ncbi.nlm.nih.gov/8662720/ DOI: 10.1074/jbc.271.22.13077","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Purified enzyme","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"338b3c45-94dd-5696-82b1-88100f4051fd","evidence_kind":"source_excerpt","locator":"Lines 267-277","start_line":267,"end_line":277,"excerpt":"### folate-fpgs-dhf-substrate\nDihydrofolate was also an effective substrate for purified human cytosolic FPGS.\nCondition category: normal\nnutrient_topic: Folate and folic acid research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Polyglutamate tails can be attached before DHF is reduced.\norganism: Homo sapiens protein expressed in Escherichia coli\ntissue_or_cell_type: Purified enzyme\nexperimental_model: Purified human cytosolic FPGS expressed in bacteria\nlimitations: Does not establish net DHF pool size in human tissues.\nexposure: Comparative substrate enzyme assays\n[chen1996] Purification and properties of human cytosolic folylpoly-gamma-glutamate synthetase and organization, localization, and differential splicing of its gene (1996). https://pubmed.ncbi.nlm.nih.gov/8662720/ DOI: 10.1074/jbc.271.22.13077","model_system":"Purified human cytosolic FPGS expressed in bacteria","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. 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