{"id":"98623834-8269-53ff-a0ab-36e2dd8db865","stable_key":"548ab9d6-3a9b-5bed-879c-17d03813b636:transport-flad1-magnesium-requirement","predicate":"supports","statement":"Purified human FADS2 showed a strict MgCl2 requirement in the reported spectrophotometric FAD-synthesis assay.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"positive","is_public":true,"mechanism_event_id":"03b6dcf6-cd3a-5175-98c7-3f40241d41ab","mechanism_event_label":"Magnesium supports enzymatic conversion of FMN into FAD.","subject":{"id":"bff427ab-35f9-59c2-bb24-fd5953bbaec2","slug":"magnesium-ion","display_name":"Mg2+","entity_type_key":"ion"},"object":{"id":"992093d2-2665-50b6-8681-95705f09322b","slug":"flad1-isoform-2","display_name":"Human FAD synthetase isoform 2","entity_type_key":"protein"},"evidence_count":1,"mechanism_event":{"id":"03b6dcf6-cd3a-5175-98c7-3f40241d41ab","stable_key":"548ab9d6-3a9b-5bed-879c-17d03813b636:transport-flad1-magnesium-requirement-event","event_type":"biochemical_relationship","label":"Magnesium supports enzymatic conversion of FMN into FAD.","description":"Purified human FADS2 showed a strict MgCl2 requirement in the reported spectrophotometric FAD-synthesis assay.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"bff427ab-35f9-59c2-bb24-fd5953bbaec2","slug":"magnesium-ion","display_name":"Mg2+","entity_type_key":"ion"},"role":"required-assay-cofactor","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"992093d2-2665-50b6-8681-95705f09322b","slug":"flad1-isoform-2","display_name":"Human FAD synthetase isoform 2","entity_type_key":"protein"},"role":"enzyme","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"d3eacf85-1a35-546d-bd30-161474dd9691","slug":"fmn","display_name":"Flavin mononucleotide","entity_type_key":"small_molecule"},"role":"substrate","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"e2cd7179-f218-54e8-9ce9-7a836ae35fac","slug":"fad","display_name":"FAD","entity_type_key":"small_molecule"},"role":"product","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""}]},"contexts":[{"dimension":"cross_nutrient","value_text":"Magnesium is a cofactor for a vitamin B2 activation step.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"evidence_location","value_text":"Abstract and activity assay","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Recombinant human FADS2 expressed in E. coli and purified","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"MgCl2 requirement tested in purified enzyme assays.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Assay-specific metal dependence does not quantify human dietary magnesium effects on flavins.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Riboflavin research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"riboflavin","display_name":"Riboflavin (vitamin B2)","entity_type_key":"small_molecule"}},{"dimension":"organism","value_text":"Homo sapiens protein","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"Magnesium supports enzymatic conversion of FMN into FAD.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[transport-fads2-2007] Over-expression in Escherichia coli, purification and characterization of isoform 2 of human FAD synthetase. (2007). https://doi.org/10.1016/j.pep.2006.09.002 DOI: 10.1016/j.pep.2006.09.002","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":"a1a2561a-0edd-5575-b289-4fbbb24cbb98","evidence_kind":"source_excerpt","locator":"Lines 333-345","start_line":333,"end_line":345,"excerpt":"### transport-flad1-magnesium-requirement\nPurified human FADS2 showed a strict MgCl2 requirement in the reported spectrophotometric FAD-synthesis assay.\nCondition category: normal\nnutrient_topic: Riboflavin research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Magnesium supports enzymatic conversion of FMN into FAD.\norganism: Homo sapiens protein\ntissue_or_cell_type: Purified enzyme\nexperimental_model: Recombinant human FADS2 expressed in E. coli and purified\nlimitations: Assay-specific metal dependence does not quantify human dietary magnesium effects on flavins.\nexposure: MgCl2 requirement tested in purified enzyme assays.\ncross_nutrient: Magnesium is a cofactor for a vitamin B2 activation step.\nevidence_location: Abstract and activity assay\n[transport-fads2-2007] Over-expression in Escherichia coli, purification and characterization of isoform 2 of human FAD synthetase. 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