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( S)-4-chloro-3-hydroxybutanoate (( S)-CHBE) is an important chiral intermediate to synthesize the side chain of cholesterol-lowering drug atorvastatin. To biosynthesize the ( S)-CHBE, a recombinant Escherichia coli harboring the carbonyl reductase and glucose dehydrogenase was successfully constructed. The recombinant E. coli was cultured in a 500-L fermentor; after induction and expression, the enzyme activity and cell biomass were increased to 23,661.65 U/L and 13.90 g DCW/L which was 3.24 and 2.60-folds compared with those in the 50 L fermentor. The biocatalytic process for the synthesis of ( S)-CHBE in an aqueous-organic solvent system was constructed and optimized with a substrate fed-batch strategy. The ethyl 4-chloro-3-oxobutanoate concentration reached to 1.7 M, and the ( S)-CHBE with yield of 97.2 % and enantiomeric excess ( e.e.) of 99 % was obtained after 4-h reaction in a 50-L reactor. In this study, the space-time yield and space-time yield per gram of biomass (dry cell weight, DCW) were 413.17 mM/h and 27.55 mM/h/g DCW for ( S)-CHBE production, respectively, which were the highest values as compared to previous reports. Finally, ( S)-CHBE was extracted from the reaction mixture with 82 % of yield and 95 % of purity. This study paved the foundation for the upscale production of ( S)-CHBE by biocatalysis method. [ABSTRACT FROM AUTHOR]