The invention discloses a construction method and application of a
gene engineering strain for producing (R,R)-2,3-
butanediol. The method comprises the following steps of carrying out
codon optimization on
nucleotide sequences of an alpha-acetolactic acid synthetase
gene, an alpha-acetolactic acid decarboxylase
gene and an R,R-2,3-
butanediol dehydrogenase gene, and obtaining a
gene cluster containing the three genes by utilizing an artificial synthesis method; inserting the
gene cluster into an
expression vector, so as to obtain a polycistronic recombinant
plasmid; introducing the polycistronic recombinant
plasmid into a
host bacterium E. coli, and knocking out a key gene of the synthetic
route of a main by-product, so as to obtain the
gene engineering strain for producing (R,R)-2,3-
butanediol. Raw materials used by the
engineering strain provided by the construction method are wide in sources and low in costs; the strain has no
pathogenicity; the strain is high in yield and high in production efficiency for the (R,R)-2,3-butanediol, has the highest yield which can reach 93.5g / L and the optical purity which can reach 99 percent or above. According to the construction method, non-grain cassava
meal and a low-cost
nitrogen source are also utilized as
fermentation raw materials for producing the (R,R)-2,3-butanediol; the production cost is lowered.