P114: Efficient L-valine production by metabolically engineered Escherichia coli W strain

Escherichia coli W strain, which possesses useful metabolic characteristics such as less acetic acid production and high L-valine tolerance, was metabolically engineered for the efficient production of L-valine. The engineered E. coli W (ΔlacI ΔilvA) strain overexpressing the ilvBN^mut, ilvCED, ygaZH and lrp genes was able to produce an impressively high concentration of 60.7 g/L L-valine by fed-batch culture in 29.5 h, resulting in a high volumetric productivity of 2.06 g/L/h. The results obtained in this study suggest that E. coli W can be a good alternative to Corynebacterium glutamicum and E. coli K-12, which have so far been the most efficient L-valine producer. Furthermore, it is expected that various bioproducts including other amino acids might be more efficiently produced by this revisited platform strain of E. coli.[This work was supported by the Advanced Biomass R&D Center (ABC) of Korea Grant funded by the Ministry of Education, Science and Technology (2010-0029799). Further supports by the World Class University Program (R32-2008-000-10142-0) of the MEST were appreciated.]