Improving Precursor Supply and Optimizing the Fermentation Process for High-Level Production of Docosapentaenoic Acid in <i>Yarrowia Lipolytica</i>

Docosapentaenoic acid (DPA) is widely applied in medicine and health products because of its important physiological functions. Using microbial cell factories for DPA production is considered a viable alternative to extracting DPA from seal oil. In this study, an engineering strategy for the efficient production of DPA was developed. First, the DPA biosynthesis pathway was successfully established in <i>Yarrowia lipolytica</i>. Then, the increase of acetyl-CoA by engineering citrate metabolism and malonyl-CoA by introducing a new orthogonal malonyl-CoA synthesis pathway was to further enhance DPA production. Furthermore, overexpression of glucose-6-phosphate dehydrogenase (G6PDH) and malic enzyme (ME) enhanced NADPH availability. Finally, by optimizing the fermentation conditions, the DPA content of the engineered strain reached 40.0%, and the yield reached 13.0 g/L in the 5 L bioreactor, representing the highest levels reported so far in <i>Y. lipolytica</i>. This study provides a promising strategy to construct microbial cell factories for fatty acid biosynthesis.