earticle

영어

We have previously developed an Escherichia coli strain which is 100% genetically defined, producing high-yield L-valine in batch culture by targeted genome engineering combined with transcriptome analysis and gene knock-out simulation of the in silico genome-scale
metabolic network. This engineered strain was able to produce 7.55 g/L L-valine with 20 g/L glucose, resulting in an impressively high yield of 0.378 g L-valine per g glucose. In this study, the development of a fed-batch fermentation process based on in silico simulation was
carried out. The results obtained here clearly demonstrate that the trade-off between L-valine and biomass formation should be optimized specifically towards L-valine production. Finally, the fedbatch culture of the further engineered strain allowed production of high concentration of 35.0 g/L L-valine. To our knowledge, the Lvaline concentration obtained here is the highest concentration ever reported in E. coli. [This work was supported by the Korean Systems
Biology Research Project (20090065571) of the Ministry of Education, Science and Technology (MEST).]