Fig. 4

Compatible combination of upstream l-phenylalanine pathway and downstream 3-phenylpropanol pathway via chromosome engineering. A Overview of the upstream l-phenylalanine pathway in E. coli. B Enhancing the upstream pathway for l-phenylalanine biosynthesis from glucose by combinatorial chromosome engineering. Production of L-phenylalanine was detected after 36 h of fermentation. C Compatibility examination of the designed downstream pathway combining with the various modified upstream l-phenylalanine pathways for de novo production of 3-phenylpropanol from 10 g/L glucose. The inducer IPTG was added at a concentration of 0.01 mM. The performance was evaluated after 30 h of fermentation. Abbreviations: 6-P-G 6-phosphate d-glucose, PEP phosphoenolpyruvate, E4P erythrose 4-phosphate, DAHP 3-deoxy-arabino-heptulonate 7-phosphate, CHA chorismic acid, 4HPP 4-hydroxyphenylpyruvate, fbr feedback inhibition resistance