Metabolic Engineering for Acetate Control in Large Scale Fermentation
Escherichia coli is the most commonly used microorganism for production of recombinant proteins for different applications. Acetate accumulation during aerobic growth on glucose has significant negative impact on recombinant protein production in Escherichia coli. Various strategies, such as process and genetic approaches have been developed to limit acetate formation to increase the productivity of recombinant proteins. We developed a strategy to combine inactivation of pyruvate oxidase (poxB) and over-expression of acety-CoA synthetase (acs) in E. coli K strain for controlling acetate accumulation. A recombinant peptide was expressed and produced in the engineered strains with a very low acetate formation in a 10-L fermentation process.
Key wordsAcetate accumulation Recombinant protein Pyruvate oxidase Acetyl-CoA synthetase Metabolic engineering P1 transduction
This work was done at DuPont. Yong Tao was responsible for engineering the poxB knockout; Qiong Cheng was responsible for engineering the acs overexpression; Alexander Kopatsis was responsible for fermentation evaluation. The authors thank Professor Barry Wanner for providing Lambda Red strains and plasmids used in this work. We also want to thank Timothy Schwartz, Qi Chen and Neal Perkins for their technical assistance.
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