Fig. 2

Engineering strategies for enhancing L-valine production in model organisms as microbial cell factories. L-valine is an essential branched chain amino acid that is widely used in industrial application. Most metabolically engineered strains prefer to use first generation feedstock such carbohydrate (glucose) as sole carbon and energy source. The choice of renewable carbon sources is also expanding and possibly, lignocellulosic raw material such as xylose and other carbon source; glycerol can be used for improved L-valine production. With the advancement of engineering, it is possible to streamline platform microorganisms such as C. glutamicum, E. coli and B. subtilis for better performance in terms of titer, productivity and yield