Green and scalable synthesis of chiral aromatic alcohols through an efficient biocatalytic system

Abstract

Summary Chiral aromatic alcohols have received much attention due to their widespread use in pharmaceutical industries. In the asymmetric synthesis processes, the excellent performance of alcohol dehydrogenase makes it a good choice for biocatalysts. In this study, a novel and robust medium‐chain alcohol dehydrogenase RhADH from Rhodococcus R6 was discovered and used to catalyse the asymmetric reduction of aromatic ketones to chiral aromatic alcohols. The reduction of 2‐hydroxyacetophenone (2‐HAP) to (R)‐(‐)‐1‐phenyl‐1,2‐ethanediol ((R)‐PED) was chosen as a template to evaluate its catalytic activity. A specific activity of 110 U mg−1 and a 99% purity of e.e. was achieved in the presence of NADH. An efficient bienzyme‐coupled catalytic system (RhADH and formate dehydrogenase, CpFDH) was established using a two‐phase strategy (dibutyl phthalate and buffer), which highly raised the tolerated substrate concentration (60 g l−1). Besides, a broad range of aromatic ketones were enantioselectively reduced to the corresponding chiral alcohols by this enzyme system with highly enantioselectivity. This system is of the potential to be applied at a commercial scale.

Efficient and scalable synthesis of 1,5-diamino-2-hydroxy-pentane from l-lysine via cascade catalysis using engineered Escherichia coli

“…The engineered E. coli strains were cultured and induced as described in the Additional file 1 , High-density fermentation for the engineered strains with modifications [ 49 ]. Fed-batch bioconversion was conducted in a 5-L fermenter in a total reaction volume of 3 L at 30 °C and 300 rpm.…”

Rhodococcus strains as a good biotool for neutralizing pharmaceutical pollutants and obtaining therapeutically valuable products: Through the past into the future

“…(Hanson et al, 2005;Liu et al, 2006;Petukhova et al, 2017;Chen et al, 2020;Hibi et al, 2021;Zhang et al, 2021bZhang et al, ). 10.3389/fmicb.2022 Frontiers in Microbiology 07 frontiersin.org Thus, 2-hydroxyacetophenone was successfully converted to (R)-(-)-1-phenyl-1,2-ethanediol (99% ee), an important pharmaceutical precursor (Han et al, 2021). The zinc-dependent alcohol dehydrogenase from R. erythropolis DSM 43297 (ReADH) converted ethyl 2-oxo-4-phenylbutyrate to ethyl 2-hydroxy-4-phenylbutanoate, an important intermediate for anti-hypertension drugs such as enalaprilat and lisinopril (Dhoke et al, 2020).…”

“…Although relatively simple and frequently used, whole-cell processes have a significant disadvantage since the target catalytic reaction is influenced by other metabolic reactions, leading to other by-products that affect the separation and purification of target products ( Şahin, 2019 ; Han et al, 2021 ). This can be avoided by using isolated enzymes.…”

“…Another example is the use of a bienzyme–coupled catalytic system composed of Rhodococcus sp. R6 alcohol dehydrogenase RhADH and Candida parapsilosis C5 formate dehydrogenase ( Han et al, 2021 ). This enzyme complex catalyzed the asymmetric reduction of 2’-hydroxyacetophenone to ( R )-(-)-1-phenyl-1,2-ethanediol with 99% ee .…”

Sequential resolution of (S) and (R)-6-fluoro-chroman-2-carboxylic acid by two esterases in turn

“…Considering that chromatographically purified enzymes are expensive for industrial applications, enzymes were studied in the lyophilized cell 22,23 form in the following experiments. In order to meet the technical demands of high stereoselectivity and product concentrations, the biocatalytic conditions necessary for the production of optically pure FCCAs were optimized.…”