The invention relates to the field of
synthetic biology,
metabolic engineering and
fermentation engineering, and discloses a
genetically engineered bacterium and application thereof in production of alpha-
ketoglutaric acid.The
genetically engineered bacterium comprises the steps that the
genetically engineered strain with
escherichia coli BW25113 or
corynebacterium glutamicum ATCC13032 as a host is constructed; overexpression type
isocitrate dehydrogenase genes are integrated through chromosomes, alpha-
ketoglutarate dehydrogenase complex genes are knocked out, NADPH
invertase is overexpressed through plasmids, and exogenous AKG
transporter protein is introduced, so that metabolic flux directional regulation and control and product
efflux enhancement are realized; meanwhile, a staged
fermentation process is adopted and comprises dynamic gradient adjustment of
inorganic phosphorus concentration and two-stage
pH control. According to the method, the AKG yield of 78.2 g / L can be obtained under the 5L tank scale, the
sugar acid conversion rate reaches 0.68, and the method has the advantages of being high in yield, low in byproduct and controllable in cost. The obtained AKG is suitable for a plurality of fields such as medical intermediates, functional foods and
cell culture additives, and has wide industrial application prospects.