The application provides a
genetically engineered bacterium with high yield of dihydroquercetin, a preparation method and application thereof, relates to the technical field of
genetic engineering, and comprises a
malonyl coenzyme A synthesis module, a
tyrosine deaminase expression module, a
naringenin synthesis module and a dihydroquercetin post-modification module. The enzymatic property of the
fusion protein is increased by about 50% of the
enzyme activity before fusion, the activity of converting
naringenin into dihydroquercetin is greatly improved, and finally the yield of dihydroquercetin expressed in
cyanobacteria is greatly improved. Meanwhile, BauA, MCR-C, Sam8, 4CL, CHS, CHI and expression
fusion protein N33'H are expressed in
cyanobacteria. The yield of dihydroquercetin is greatly increased under
seawater culture conditions. The technical problem that the yield of biosynthetic dihydroquercetin is low and cannot meet the requirements of industrial application in the prior art is solved.