title: D-Aminoaciduria in mutant mice lackingD-amino-acid oxidase activity.
abstract: Urine of mutant ddY/DAO(-) mice lackingD-amino-acid oxidase activity contained more serine and proline than that of normal ddY/DAO(+) mice.D-Amino-acid oxidase treatment of urinary amino acids decreased the serine and proline, suggesting that they containedD-isomers. An HPLC analysis confirmed the presence ofD-serine. Urinary serine and proline contents were not decreased when the ddY/DAO(-) mice were fed a diet which did not contain supplementaryD-methionine or when they were given water containing antibiotics. These results suggest that theD-serine andD-proline do not derive from theD-methionine supplemented in the diet or from intestinal bacteria. In urine of the ddY/DAO(-) mice, a substance which seemed to beD-methionine sulfoxide and/orD-methionine sulfone was present. It is probably a metabolite of theD-methionine supplemented in the diet. TheD-aminoaciduria in the mutant mice lackingD-amino-acid oxidase activity indicates that this enzyme is involved in the metabolism of theD-amino acids in normal mice.
authors.affiliation: Department of Microbiology, Dokkyo University School of Medicine, 321-02, Mibu, Tochigi, Japan.
authors.forename: R
authors.initials: R
authors.lastname: Konno
authors.forename: M
authors.initials: M
authors.lastname: Ikeda
authors.forename: A
authors.initials: A
authors.lastname: Niwa
authors.forename: Y
authors.initials: Y
authors.lastname: Yasumura