XU Hongmei, XIA Shiwen1, HE Conglin
(School of Bioinformatics, Chongqing University of Posts and Telecommunications, Chongqing 400065, China)
Abstract: The D-enantiomer of DL-amino acid is oxidative deaminated enantioselectively into the corresponding oxo acid by immobilized D-amino acid oxidase (D-AAO) in the presence of catalase and oxygen, and the L-enantiomer is retained. The substrate specificity of D-AAO was studied and the reaction conditions were optimized. The results showed that D-AAO has a broader substrate spectrum and is capable of catalyzing the oxidative deaminzation of hydrophobic D-α-amino acids. Under the optimal conditions, L-2-aminobutyric acid and L-2-aminovaleric acid were obtained in 48% and 47% yield , 99.5% and 99.8% ee respectively. Furthemore, the yields of L-2-aminobutyric acid and L-2-aminovaleric acid were improved and their optically purity were retained through in-situ reduction of imine acids produced during the oxidative deaminization by Pd-C/HCOONH4.
Key words: Immobilized D-amino acid oxidase; Catalase; Oxidative deamination; DL-amino acids; Non-natural amino acids
E-mail: xiasw@cqupt.edu.cn
Journal of Molecular Catalysis, Vol. 26, Issue 2, 2012, 192-196
