{"id":"0b1b4a3f-62cc-53ab-96d3-7ea0bd229932","stable_key":"548ab9d6-3a9b-5bed-879c-17d03813b636:b2-mthfr-glu429ala-retention","predicate":"preserves","statement":"Glu429Ala MTHFR showed FAD-release behavior indistinguishable from wild type under the tested dilution conditions.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"neutral","is_public":true,"mechanism_event_id":"312a1b54-c969-5c5b-9dc4-2dc3d72b7e4f","mechanism_event_label":"The two common MTHFR variants did not share the same cofactor-retention phenotype.","subject":{"id":"48c82cea-3284-5c81-b14b-d774bd25c118","slug":"mthfr-glu429ala","display_name":"MTHFR Glu429Ala protein","entity_type_key":"protein_state"},"object":{"id":"e2cd7179-f218-54e8-9ce9-7a836ae35fac","slug":"fad","display_name":"FAD","entity_type_key":"small_molecule"},"evidence_count":1,"mechanism_event":{"id":"312a1b54-c969-5c5b-9dc4-2dc3d72b7e4f","stable_key":"548ab9d6-3a9b-5bed-879c-17d03813b636:b2-mthfr-glu429ala-retention-event","event_type":"biochemical_relationship","label":"The two common MTHFR variants did not share the same cofactor-retention phenotype.","description":"Glu429Ala MTHFR showed FAD-release behavior indistinguishable from wild type under the tested dilution conditions.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"9fc32b1a-0f08-544c-a361-1c728203b6ec","slug":"mthfr","display_name":"Methylenetetrahydrofolate reductase / MTHFR","entity_type_key":"protein"},"role":"wild-type comparator","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"e2cd7179-f218-54e8-9ce9-7a836ae35fac","slug":"fad","display_name":"FAD","entity_type_key":"small_molecule"},"role":"measured cofactor","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"48c82cea-3284-5c81-b14b-d774bd25c118","slug":"mthfr-glu429ala","display_name":"MTHFR Glu429Ala protein","entity_type_key":"protein_state"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""}]},"contexts":[{"dimension":"cross_nutrient","value_text":"Bounds extrapolation of B2-cofactor loss across MTHFR variants.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"evidence_location","value_text":"Results: FAD loss; Figs 1-3","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Baculovirus-produced purified human wild-type, Ala222Val, Glu429Ala and double-mutant MTHFR; dilution/cofactor-release assays.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"Purified-enzyme assay","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Normal result under tested in-vitro conditions does not exclude all cellular effects of A1298C.","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","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"The two common MTHFR variants did not share the same cofactor-retention phenotype.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[yamada2001] Effects of common polymorphisms on the properties of recombinant human methylenetetrahydrofolate reductase. (2001). https://pubmed.ncbi.nlm.nih.gov/11742092/ DOI: 10.1073/pnas.261469998","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Purified recombinant enzyme; no intact tissue","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"39eaeed3-71b8-5f69-a392-468849b0adaf","evidence_kind":"source_excerpt","locator":"Lines 1080-1092","start_line":1080,"end_line":1092,"excerpt":"### b2-mthfr-glu429ala-retention\nGlu429Ala MTHFR showed FAD-release behavior indistinguishable from wild type under the tested dilution conditions.\nCondition category: normal\nnutrient_topic: Riboflavin research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: The two common MTHFR variants did not share the same cofactor-retention phenotype.\norganism: Homo sapiens\ntissue_or_cell_type: Purified recombinant enzyme; no intact tissue\nexperimental_model: Baculovirus-produced purified human wild-type, Ala222Val, Glu429Ala and double-mutant MTHFR; dilution/cofactor-release assays.\nlimitations: Normal result under tested in-vitro conditions does not exclude all cellular effects of A1298C.\nexposure: Purified-enzyme assay\ncross_nutrient: Bounds extrapolation of B2-cofactor loss across MTHFR variants.\nevidence_location: Results: FAD loss; Figs 1-3\n[yamada2001] Effects of common polymorphisms on the properties of recombinant human methylenetetrahydrofolate reductase. 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