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Updated: May 23, 2026
Enzymatic Cascade Reactions for the Synthesis of Chiral Amino Alcohols from L-lysine
Published on: February 16, 2018
[Cloning, expression and characterization of chiral alcohol dehydrogenase from Rhodococcus erythropolis ATCC 4277]
Qinghe Zhu1, Honghua Jia, Yan Li
1College of Biotechnology and Pharmaceutical Engineering, Nanjing University of Technology, State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing 211816, China. zqh021@yahoo.com.cn
Objective:
We characterized alcohol dehydrogenase from Rhodococcus erytropolis to catalyze ketoesters or ketones.
Methods:
We cloned alcohol dehydrogenase gene (adh) of 1047 bp from Rhodococcus erythropolis ATCC 4277, inserted the open reading frame of adh into vector pET-22b(+) and expressed in auto-inducing media for 24 h at 15 degrees C. The enzyme activity was determined at 30 degrees C using acetophenone as substrate.
Results:
Under the above conditions, the specific enzyme activity of crude extract was 2.6 U/mg. The optimal pH was between 6.0 and 6.5 and the enzyme can survived up to 60 degrees C. After incubation at 60 degrees C for 5 h, 80% enzyme activity remained. The optimal substrate among beta-ketoesters examined was ethyl acetoaetate. Ethyl 4-chloroacetoacetate was catalyzed by whole cell in aqueous phase. After chiral liquid chromatography, the product showed (R)-enantioselective.
Conclusion:
The study shows that the enzyme might have potential in beta-ketoesters transformation on industrial scale.
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