l-Lysine stands out as one of the most rapidly expanding products in the feed amino acid market. However, the undefined genetic backgrounds of existing l-lysine hyperproducing Escherichia coli strains have impeded their further optimization. In this study, an l-lysine hyperproducer was constructed de novo via the precise modification of just 12 genomic targets on the wild-type E. coli model strain MG1655. The final engineered strain achieved an l-lysine titer, rate, and yield (TRY) of 85 g/L, 1.77 g/L/h, and 0.55 g/g glucose in fed-batch fermentation, respectively, representing the highest TRY ever reported for a genetically defined E. coli. This work identifies a de novo engineered specific genotype that enables l-lysine hyperproduction in E. coli, offering a pivotal platform strain to drive both the subsequent optimization and the mechanistic dissection of l-lysine biosynthetic regulation.
Zhou et al. (Wed,) studied this question.