10.6084/m9.figshare.8180672.v1
Lu Dong
Lu
Dong
Yongkai Xu
Yongkai
Xu
Yun Zhang
Yun
Zhang
Aijun Sun
Aijun
Sun
Yunfeng Hu
Yunfeng
Hu
Enantioselective resolution of (±)-1-phenylethyl acetate by extracellular proteases from deep-sea bacterium <i>Bacillus</i> sp. DL-2
Taylor & Francis Group
2019
Asymmetric hydrolysis
extracellular proteases
immobilization
marine microorganisms
(R)-1-phenylethanol
(S)-1-phenylethyl acetate
2019-05-24 06:05:20
Journal contribution
https://tandf.figshare.com/articles/journal_contribution/Enantioselective_resolution_of_-1-phenylethyl_acetate_by_extracellular_proteases_from_deep-sea_bacterium_i_Bacillus_i_sp_DL-2/8180672
<p>Chiral 1-phenylethanol and its ester derivative are important chiral chemicals in diverse industries and the preparation of those optically pure enantiomers is of great importance. One bacterium, <i>Bacillus</i> sp. DL-2, whose extracellular proteases could efficiently asymmetrically hydrolyse (±)-1-phenylethyl acetate, was isolated from the deep sea of the Western Pacific. After the immobilization of extracellular proteases and the optimization of enzymatic reactions, (<i>R</i>)-1-phenylethanol was prepared with the enantiomeric excess (<i>e.e</i>.) being 97% and the yield being 41%, respectively. The optimal resolution reaction condition for the preparation of (<i>R</i>)-1-phenylethanol using immobilized extracellular proteases was found to be 5-mM (±)-1-phenylethyl acetate, 360 mg/mL immobilized extracellular proteases, pH 6.5, and 20 °C for 2 h. (<i>S</i>)-1-phenylethyl acetate was generated through enzymatic kinetic resolution with the <i>e.e.</i> being as high as 99% and the yield being 71%, respectively. The optimal resolution reaction condition for the preparation of (<i>S</i>)-1-phenylethyl acetate was found to be 2.5-mM (±)-1-phenylethyl acetate, 440 mg/mL immobilized extracellular proteases, pH 7.5, and 35 °C for 10 h. Our report is the first report about the kinetic resolution of (±)-1-phenylethyl acetate using proteases and the enantio-preference of the proteases was found to be the same as those of most other esterases/lipases. Also notably, the optical purity of (<i>S</i>)-1-phenylethyl acetate generated through kinetic resolution using the proteases of <i>Bacillus</i> sp. DL-2 was the highest report so far. Proteases from deep-sea <i>Bacillus</i> sp. DL-2 are new contributions to the biocatalyst library for the preparation of valuable chiral alcohols and chiral esters through kinetic resolution.</p>