Abstract:Pyruvate is an important organic acid, which plays an important role in the energy metabolism of organisms. As a precursor, pyruvate can participate in the biosynthesis of many organic compounds. Therefore, the metabolic engineering strategy was used to modify corynebacterium glutamate to produce pyruvate. First, five key genes related to pyruvate metabolism tributaries of Corynebacterium glutamicum were successfully knocked out by homologous recombination method: pyruvate quinone oxidoreductase gene pqo, pyruvate carboxylase gene pyc, aminotransferase gene alaT, valine-pyruvate aminotransferase gene avtA, pyruvate dehydrogenase gene aceE. The yield of pyruvate reached 14.64 g/L after 72 h of shaking flask fermentation. In order to further increase the metabolic flux of pyruvate pathway, transketolase gene tkt, transaldolase gene tal, phosphoenolpyruvate carboxykinase gene pck were overexpressed to increase the supply of precursors for pyruvate synthesis. Finally, the yield of pyruvate reached 15.39 g/L after 72 h shaker fermentation, which was 28 times higher than that of the wild-type strain, which is helpful to provide theoretical basis and reference for the future study on the production of pyruvate by microbial fermentation.