AUTHOR=Zhang Dong , Lei Yuqing , Wang Tingting , Lin Wenqian , Chen Xingyi , Wu Minchen 

TITLE=Gram-Scale Synthesis of (R)-P-Chlorophenyl-1,2-Ethanediol at High Concentration by a Pair of Epoxide Hydrolases

JOURNAL=Frontiers in Bioengineering and Biotechnology

VOLUME=10

YEAR=2022

URL=https://www.frontiersin.org/journals/bioengineering-and-biotechnology/articles/10.3389/fbioe.2022.824300

DOI=10.3389/fbioe.2022.824300

ISSN=2296-4185

ABSTRACT=<p>(<italic>R</italic>)-<italic>p</italic>-chlorophenyl-1,2-ethanediol (<italic>p</italic>CPED) is an important intermediate for the synthesis of (<italic>R</italic>)-eliprodil that is widely applied in the treatment of ischemic stroke. To prepare (<italic>R</italic>)-<italic>p</italic>CPED with high enantiomeric excess (<italic>ee</italic><sub>p</sub>) and yield via the enantioconvergent hydrolysis of racemic styrene oxide (<italic>rac-p</italic>CSO) at high concentration, the bi-enzymatic catalysis was designed and investigated by a pair of epoxide hydrolases, a mutant (<italic>Pv</italic>EH1<sup>Z4X4-59</sup>) of <italic>Phaseolus vulgaris</italic> EH1 and a mutant (<italic>Rp</italic>EH<sup>F361V</sup>) of <italic>Rhodotorula paludigena Rp</italic>EH<italic>.</italic> Firstly, the maximum allowable concentration of <italic>rac</italic>-<italic>p</italic>CSO was confirmed. Subsequently, the addition mode and the weight ratio of two <italic>Escherichia coli</italic> cells were optimized. Finally, under the optimized reaction conditions—the cell weight ratio 20:1 of <italic>E. coli</italic>/<italic>pveh</italic>1<sup>z4x4-59</sup> to <italic>E. coli/rpeh</italic><sup>F361V</sup>, a simultaneous addition mode, and reaction temperature at 25°C—300 mM <italic>rac-p</italic>CSO in the 100 ml 4% (v/v) Tween-20/phosphate buffer system (100 mM, pH 7.0) was completely hydrolyzed within 5 h, affording (<italic>R</italic>)-<italic>p</italic>CPED with 87.8% <italic>ee</italic><sub>p</sub>, 93.4% yield, and 8.63 g/L/h space–time yield (STY). This work would be an efficient technical strategy for the preparation of chiral vicinal diols at industrial scale.</p>