Systematic metabolic engineering of Yarrowia lipolytica for the enhanced production of erythritol.

In recent times, there has been a growing interest in exploring microbial strains that exhibit enhanced erythritol productivity. Nonetheless, the lack of advanced synthetic biology tools has limited rapid strain development. In this study, the CRISPR/Cas9 system was employed to genetically modify Yarrowia lipolytica at the chromosomal level, which could improve the production of erythritol while saving the time required to markers recovery, and realizing the rapid construction of high-erythritol strains. Firstly, the basic strain E004 was generated by increasing the efficiency of homologous recombination and regulating the erythritol degradation pathway. Secondly, eleven key gene targets and a strong promoter 8UAS1B-P was obtained by target screening and promoter engineering. Finally, based on modular pathway engineering and morphological engineering, the high production of erythritol was achieved successfully. The best-engineered strain E326 produced 256 g/L erythritol in a 5-L bioreactor, which is the highest production level reported so far in Y. lipolytica.