ID | 52123 |
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Title Alternative | Characterization of L-Arginine Oxidase Made from L-Glutamate Oxidase
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Author |
Nakai, Ryuichiro
Fujino, Shihoko
Utsumi, Tomohiro
Kusakabea, Hitoshi
Inagaki, Kenji
Kaken ID
researchmap
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Abstract | 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.
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Keywords | L-glutamate oxidase
L-arginine oxidase
biosensor
modified substrate specificity
L-amino acid oxidase
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Note | 原著論文 (Original paper)
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Published Date | 2014-02-01
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Publication Title |
岡山大学農学部学術報告
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Publication Title Alternative | Scientific Reports of the Faculty of Agriculture Okayama University
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Volume | volume103
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Publisher | 岡山大学農学部
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Publisher Alternative | Faculty of Agriculture, Okayama University
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Start Page | 5
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End Page | 9
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ISSN | 2186-7755
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Content Type |
Departmental Bulletin Paper
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language |
Japanese
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File Version | publisher
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Refereed |
False
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Eprints Journal Name | srfa
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