Cloning, expression of glutaminase from Pseudomonas nitroreducens and application to theanine synthesis. (February 2013)

• Record Type: Journal Article
• Authors: Pu, Hefang; Wang, Qi; Zhu, Fenfen; Cao, Xiang; Xin, Yinqiang; Luo, Lan; Yin, Zhimin
• Is Part Of: Biocatalysis and biotransformation. Volume 31:Number 1(2013)
• Page Start: 1
• Page End: 7
• Publication Date: 2013-02
• Subjects: Enzymes -- Biotechnology -- Periodicals; Enzymes -- Industrial applications -- Periodicals; Biotransformation (Metabolism) -- Periodicals; 660.63
• DOI: 10.3109/10242422.2012.749462
• Languages: English
• ISSNs: 1024-2422

Abstract

<abstract> <title>Abstract</title> <p>It has been reported that glutaminase (GLS) from <italic>Pseudomonas nitroreducens</italic> can be used in a new method for producing L-theanine. In this study, a pair of degenerate primers was designed to obtain the glutaminase gene from <italic>P. nitroreducens</italic> DSM 14399. The glutaminase gene (PnGLS gene) was 909 bps long encoding a protein of 302 amino acids, containing several key catalytic residues of GLSs (Ser61, Lys64, Asn111, Lys193 and Ser194). The optimum conditions for the production of theanine were 0.3 M L-glutamine, 1.5 M ethylamine and 1.5 U/5 ml recombinant PnGLS, pH 10.0 (100 mM borate buffer), 5 h incubation at 37°C. L-theanine was detected by paper chromatography or high pressure liquid chromatography (HPLC) at a concentration of 21.8 g/L reaction mixture; a yield of about 40%. Using recombinant PnGLS is a feasible route for the future industrial production of L-theanine.</p> </abstract>