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

Aim: The aim of this study is to engineer Pantoea dispersa MSC14 into a strain capable of producing lycopene and to enhance its lycopene content.

Methods and results: 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.

Conclusions: 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.