title: [Molecular basis of vitamin-responsive inborn errors of metabolism].
abstract: In inborn errors where the defective enzyme had a cofactor requirement it was found that the administration of large amounts of the vitamin resulted in a clinical and biochemical improvement. A mutation that imposes an exaggerated requirement for a vitamin affects the apoenzyme directly, the conversion of a vitamin into coenzyme, or the attachment of vitamin to the apoenzyme. Direct proof has so far been provided that molecular defects in the said gene underlie both the vitamin-responsive and vitamin-nonresponsive forms. HCS deficiency is an exception, all HCS-deficient patients being responsive to biotin administration. We examined the relationship between the kinetic characteristics of HCS mutants and the clinical and biochemical features of the HCS deficient patients.
authors.affiliation: Department of Medical Genetics, Tohoku University School of Medicine.
authors.forename: K
authors.initials: K
authors.lastname: Narisawa
mesh_terms: D019731:Carbon-Nitrogen Ligases / Q000172:deficiency* / Q000235:genetics; D006712:Homocystinuria / Q000235:genetics*; D006801:Humans; D008375:Maple Syrup Urine Disease / Q000235:genetics*; D009154:Mutation; D011736:Pyridoxine / Q000627:therapeutic use; D015325:Pyruvate Dehydrogenase Complex Deficiency Disease; D013831:Thiamine / Q000627:therapeutic use
chemical_list: D019731:Carbon-Nitrogen Ligases; C023312:holocarboxylase synthetases; D011736:Pyridoxine; D013831:Thiamine