Enzyme-catalyzed method for synthesizing (2s, 3r)-2-substituted aminomethyl-3-hydroxybutyrate

A method of synthesizing (2S, 3R)-2-substituted aminomethyl-3-hydroxybutyrate, comprising:

• (1) preparing engineered bacteria containing a carbonyl reductase SsCR-encoding gene;
• (2) preparing a resting cell suspension of the engineered bacteria;
• (3) inoculating the resting cell suspension of the engineered bacteria into a kanamycin-containing medium to prepare a supernatant containing carbonyl reductase SsCR;
• and
• (4) mixing the supernatant with 2-substituted aminomethyl-3-one butyrate (II), glucose dehydrogenase, a cosolvent, a phosphate-buffered saline, glucose and a cofactor to obtain a reaction mixture;
• and subjecting the reaction mixture to an asymmetric carbonyl reduction to obtain the (2S, 3R)-2-substituted aminomethyl-3-hydroxybutyrate (I), as shown in the following reaction scheme:
• wherein R1 is selected from the group consisting of hydrogen, tert-butoxycarbonyl, benzyloxycarbonyl, trityl, formyl, trifluoroacetyl, benzoyl, mono-substituted benzoyl, poly-substituted benzoyl and heteroaryl formyl;
• and R2 is selected from the group consisting of C1-C10 alkyl, cycloalkyl, phenethyl, substituted phenethyl, phenyl and substituted phenyl;
• and
• the carbonyl reductase SsCR has an amino acid sequence as shown in SEQ ID NO. 1, or is a carbonyl reductase that has an amino acid sequence with greater than 80% identity with SEQ ID NO. 1 and maintains a catalytic activity.