title: Characterization and application of a L-specific amino acid oxidase from Rhodococcus sp. AIU LAB-3.
abstract: An L-specific amino acid oxidase (L-AAO) suitable for assay of N-acyl-L-amino acid amidohydrolase (L-aminoacylase) activity was purified from Rhodococcus sp. AIU LAB-3. The enzyme exhibited broad substrate specificity and catalyzed an oxidative deamination of the a-amino group of L-amino acids. The optimal enzyme activities for L-amino acids tested were observed in the pH range from 6.0 to 8.5, and more than 80% of the maximum activity was obtained at pH 7.5. The enzyme was stable in the pH range from 7.0 to 8.5, and the apparent Km values for those L-amino acids were small. We, therefore, developed a new enzymatic method for assay of L-aminoacylase activity using the L-AAO at pH 7.5. The new enzymatic method had advantages that the L-aminoacylase reaction was spectrophotometrically followed by measuring absorbance at 555 nm. The L-aminoacylase activity was assayed within 10 min using a small reaction volume. Thus, the new enzymatic method was simple and sensitive compared to the ninhydrin method.
authors.affiliation: Department of Biological Chemistry and Food Sciences, Faculty of Agriculture, Iwate University, 3-18-8 Ueda, Morioka 020-8550, Japan. kiso@iwate-u.ac.jp
authors.forename: Kimiyasu
authors.initials: K
authors.lastname: Isobe
authors.forename: Shiina
authors.initials: S
authors.lastname: Satou
authors.forename: Erika
authors.initials: E
authors.lastname: Matsumoto
authors.forename: Sachiko
authors.initials: S
authors.lastname: Yoshida
authors.forename: Miwa
authors.initials: M
authors.lastname: Yamada
authors.forename: Makoto
authors.initials: M
authors.lastname: Hibi
authors.forename: Jun
authors.initials: J
authors.lastname: Ogawa
mesh_terms: D000581:Amidohydrolases / Q000378:metabolism; D000595:Amino Acid Sequence; D050830:L-Amino Acid Oxidase / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D008969:Molecular Sequence Data; D012240:Rhodococcus / Q000201:enzymology* / Q000378:metabolism; D013379:Substrate Specificity
chemical_list: D050830:L-Amino Acid Oxidase; D000581:Amidohydrolases; C019672:aminoacylase I