The present disclosure relates to the technical field of biochemical engineering and particularly discloses a preparation method for (R)-3-hydroxyl-5-hexenoate. In the method of the present disclosure, the (R)-3-hydroxyl-5-hexenoate is prepared by catalytic reduction of 3-carbonyl-5-hexenoate by ketoreductase with 3-carbonyl-5-hexenoate as the substrate. The amino acid sequence of ketoreductase is shown in SEQ ID NO.1. In the present disclosure, the (R)-3-hydroxyl-5-hexenoate having a very high chiral purity is obtained by asymmetric reduction by ketoreductase as the biocatalyst. The present disclosure has the advantages of easy operation, mild reaction conditions, high reaction yield and good practical industrial application value.

Disclosed are an expression cassette for isopropanol production, a recombinant vector for isopropanol production expression cassette, a including the recombinant microorganism for isopropanol production into which the vector is introduced, and a method of producing isopropanol using the recombinant microorganism. The recombinant microorganism in which a succinic acid bypass metabolic pathway is introduced to an isopropanol production pathway has very high ability to produce isopropanol. The recombinant microorganism is capable of producing isopropanol in an amount corresponding to about 100 times the maximum amount of isopropanol that is produced using known Corynebacterium glutamicum, and thus can effectively produce isopropanol and can be useful in various industrial fields where isopropanol is utilized. The use of the recombinant microorganism makes possible eco-friendly production of high-value-added isopropanol materials for manufacturing biomass-derived chemical products using glucose in lieu of petroleum.