Metabolic engineering Escherichia coli for high-level production of pseudouridine

Background Pseudouridine-incorporated mRNA vaccines can enhance protein expression and reduce immunogenicity, leading to a large demand for pseudouridine to be used in the production of mRNA drugs. The production of pseudouridine by chemical or semienzymatic synthesis is limited by low yields and high costs, and the production of pseudouridine via the fermentation of genetically engineered strains is an attractive prospect. Results In the present study, a cell factory for the efficient synthesis of pseudouridine was established. First, the pyrimidine precursor biosynthesis pathway in Escherichia coli was systematically modified to increase metabolite flux to pseudouridine biosynthesis. Next, two crucial genes (pseudouridine 5’-phosphate glycosidase gene ( psuG ) and phosphatase gene) were screened. An artificial pseudouridine biosynthesis pathway with high efficiency was constructed. The accumulation of pseudouridine was further increased by the deletion of pseudouridine catabolism-related genes. Ultimately, the pseudouridine titre in a 5-L bioreactor reached 7.5 g/L. Conclusion In this study, a cell factory producing a high yield of pseudouridine was successfully constructed and showed the potential for use in industrial production.