6169-06-8Relevant articles and documents
Supported ionic liquid-like phases as efficient solid ionic solvents for the immobilisation of alcohol dehydrogenases towards the development of stereoselective bioreductions
Altava, Belen,García-Verdugo, Eduardo,Gotor-Fernández, Vicente,Lavandera, Iván,Lozano, Pedro,Luis, Santiago V.,Porcar, Raul
, p. 5609 - 5617 (2021/08/16)
Polymeric materials containing ionic liquid fragments, like those found in bulk ILs, are excellent solid media for the immobilisation of biocatalysts. Herein, the entrapment of the enzymatic system formed by alcohol dehydrogenase from Rhodococcus ruber (ADH-A) overexpressed in E. coli and its coenzyme has been studied. The activity, stability and reusability of these preparations have been investigated in the bioreduction of prochiral ketones finding excellent levels of conversion and selectivity. Interestingly, the immobilised enzyme remained active and exhibited excellent stability in aqueous solutions after several recycling uses. More importantly, these biopolymer materials retained most of their activity after consecutive reaction cycles, prolonged storage and under flow conditions.
Production of chiral alcohols from racemic mixtures by integrated heterogeneous chemoenzymatic catalysis in fixed bed continuous operation
Carceller, Jose Miguel,Climent, Maria J.,Corma, Avelino,Iborra, Sara,Mifsud, Maria
, p. 2767 - 2777 (2020/06/17)
Valuable chiral alcohols have been obtained from racemic mixtures with an integrated heterogeneous chemoenzymatic catalyst in a two consecutive fixed catalytic bed continuous reactor system. In the first bed the racemic mixture of alcohols is oxidized to the prochiral ketone with a Zr-Beta zeolite and using acetone as the hydrogen acceptor. In the second catalytic bed the prochiral ketone is stereoselectively reduced with an alcohol dehydrogenase (ADH) immobilized on a two dimensional (2D) zeolite. In this process, the alcohol (isopropanol) formed by the reduction of acetone in the first step reduces the cofactor in the second step, and the full reaction cycle is in this way internally closed with 100% atom economy. A conversion of about 95% with ～100% selectivity to either the (R) or the (S) alcohol has been obtained for a variety of racemic mixtures of alcohols.
Efficient Asymmetric Synthesis of Ethyl (S)-4-Chloro-3-hydroxybutyrate Using Alcohol Dehydrogenase SmADH31 with High Tolerance of Substrate and Product in a Monophasic Aqueous System
Chen, Rong,Liu, Qinghai,Wang, Hualei,Wei, Dongzhi,Xie, Youyu,Yang, Zeyu,Ye, Wenjie
, p. 1068 - 1076 (2020/07/06)
Bioreductions catalyzed by alcohol dehydrogenases (ADHs) play an important role in the synthesis of chiral alcohols. However, the synthesis of ethyl (S)-4-chloro-3-hydroxybutyrate [(S)-CHBE], an important drug intermediate, has significant challenges concerning high substrate or product inhibition toward ADHs, which complicates its production. Herein, we evaluated a novel ADH, SmADH31, obtained from the Stenotrophomonas maltophilia genome, which can tolerate extremely high concentrations (6 M) of both substrate and product. The coexpression of SmADH31 and glucose dehydrogenase from Bacillus subtilis in Escherichia coli meant that as much as 660 g L-1 (4.0 M) ethyl 4-chloroacetoacetate was completely converted into (S)-CHBE in a monophasic aqueous system with a >99.9% ee value and a high space-time yield (2664 g L-1 d-1). Molecular dynamics simulation shed light on the high activity and stereoselectivity of SmADH31. Moreover, five other optically pure chiral alcohols were synthesized at high concentrations (100-462 g L-1) as a result of the broad substrate spectrum of SmADH31. All these compounds act as important drug intermediates, demonstrating the industrial potential of SmADH31-mediated bioreductions.
