Gene editing technology combined with response surface optimization to improve the synthesis ability of lycopene in Pantoea dispersa MSC14

The aim of this study is to engineer Pantoea dispersa MSC14 into a strain capable of producing lycopene and to enhance its lycopene content. Our laboratory isolated the strain P. dispersa MSC14 from petroleum-contaminated soil in a mining area. Whole-genome sequencing confirmed the existence of a carotenoid synthesis pathway in this strain. This study employed an optimized CRISPR/Cas9 system to perform a traceless gene knockout of the lycopene cyclase gene crtY and to overexpress the octahydrolycopene dehydrogenase gene crtI in the P. dispersa MSC14. This strategic genetic modification successfully constructed the lycopene-producing strain MSC14-LY, which exhibited a notable lycopene content with a biomass productivity of 553 μg of lycopene per gram dry cell weight (DCW). Additionally, the components of the lycopene fermentation medium were optimized using Plackett-Burman design and response surface methodology. The average lycopene content was increased to 5.13 mg g -1 DCW in the optimized LY fermentation medium. Through genetic engineering, P. dispersa MSC14 was transformed into a strain capable of producing lycopene, achieving a yield of 5.13 mg g-1 DCW after medium optimization. Genetic engineering successfully transformed P. dispersa MSC14 into a strain capable of producing lycopene, achieving a yield of 5.13 mg g-1 DCW after medium optimization.