Method of generating 1,2,4-butantriol by in vitro enzyme reaction and application thereof

The invention discloses a method of generating 1,2,4-butantriol by the in vitro enzyme reaction and application thereof, and belongs to the technical field of bioengineering. The method provided by the invention comprises the following steps: respectively constructing genetically-engineered bacteria of over-expressed D-xylonic acid anhydrase genes, 2-keto acid decarboxylase genes and alcohol dehydrogenase genes; after carrying out fermentation cultivation on the obtained genetically-engineered bacteria, crushing thalli by ultraviolet waves; collecting crude enzyme fluid; and after carrying out mixed adjustment on concentration of D-xylonic acid anhydrase, 2-keto acid decarboxylase and alcohol dehydrogenase, adding a reaction substrate to synthesize 1,2,4-butantriol. The method provided by the invention realizes synthesis of 1,2,4-butantriol in vitro by controlling the enzyme reaction and using D-xylonic acid as the raw material and has the characteristic of good convenience for enlarging production; and the enlarged yield can reach 5.98g/L.