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ID 52123
フルテキストURL
タイトル(別表記)
Characterization of L-Arginine Oxidase Made from L-Glutamate Oxidase
著者
中井 隆一郎 岡山大学
藤野 志保子 岡山大学
内海 友宏 岡山大学
田村 隆 岡山大学
日下部 均 ㈱エンザイムセンサ
稲垣 賢二 岡山大学
抄録
 L‒Glutamate oxidase (LGOX) from Streptomyces sp. X‒119‒6 has strict substrate specificity toward L‒glutamate. Recently, we solved the X‒ray crystal structure of LGOX and this revealed that Arg305 in the active site is the key residue involved in substrate recognition. Therefore, we created 19 mutant enzymes of R305X‒LGOX by saturation mutagenesis. One of them R305D‒LGOX, Arg305 substituted with Asp exhibited oxidase activity for L‒Arg. Optimum pH of R305D‒LGOX mutant enzyme was pH 8.5. Interestingly, the activity of R305D‒LGOX toward L‒Arg was inhibited by phosphate. And furthermore, the substrate specificity of R305D‒LGOX was affected by using buffer. The results of inhibition analysis suggest, that phosphate is a competitive inhibitor of R305D‒LGOX when L‒Arg is used as substrate. Kinetic analysis of R305D‒LGOX showed that Km value and kcat value of R305D‒LGOX toward l-Arg were 0.68 mM and 6.7 s-1 respectively. In this study, we showed that R305D‒LGOX mutant enzyme is a novel l-arginine oxidase and useful for l-arginine biosensor.
キーワード
L-glutamate oxidase
L-arginine oxidase
biosensor
modified substrate specificity
L-amino acid oxidase
備考
原著論文 (Original paper)
発行日
2014-02-01
出版物タイトル
岡山大学農学部学術報告
出版物タイトル(別表記)
Scientific Reports of the Faculty of Agriculture Okayama University
103巻
出版者
岡山大学農学部
出版者(別表記)
Faculty of Agriculture, Okayama University
開始ページ
5
終了ページ
9
ISSN
2186-7755
資料タイプ
紀要論文
言語
Japanese
論文のバージョン
publisher
査読
無し
Eprints Journal Name
srfa