Preparation method of (2S,3S)-2,3-butanediol

The invention discloses a preparation method of (2S,3S)-2,3-butanediol, and belongs to the technical field of biochemistry. The preparation method comprises the following steps of: stirring and mixingsolution containing ketoreductase with buffer solution to obtain mixed solution; in the stirring process, adding nicotinamide adenine dinucleotide, isopropanol and 2,3-butanedione into the mixed solution to perform closed reaction, so that reaction solution is obtained; carrying out reduced pressure suction filtration and rotary evaporation treatment on the reaction solution to obtain extractingsolution; and carrying out rectification separation on the extracting solution to obtain the (2S,3S)-2,3-butanediol. Meanwhile, the invention provides an amino acid sequence of the ketoreductase for catalyzing 2,3-butanedione to generate the (2S,3S)-2,3-butanediol. The invention further provides a nucleotide sequence for coding the ketoreductase. The preparation method is simple in synthetic routeand high in efficiency; 2,