Efficient Mycoprotein Production with Low CO2 Emissions through Metabolic Engineering and Fermentation Optimization of Fusarium venenatum.

ABSTRACT

The global protein shortage is intensifying, and promising means to ensure daily protein supply are desperately needed. The mycoprotein produced by Fusarium venenatum is a good alternative to animal/plant-derived protein. To comprehensively improve the mycoprotein synthesis, a stepwise strategy by blocking the byproduct ethanol synthesis and the gluconeogenesis pathway and by optimizing the fermentation medium was herein employed. Ultimately, compared to the wild-type strain, the synthesis rate, carbon conversion ratio, and protein content of mycoprotein produced from the engineered strain were increased by 57% (0.212 vs 0.135 g/L·h), 62% (0.351 vs 0.217 g/g), and 57% (61.9 vs 39.4%), respectively, accompanied by significant reductions in CO2 emissions. These results provide a referential strategy that could be useful for improving mycoprotein synthesis in other fungi; more importantly, the obtained high-mycoprotein-producing strain has the potential to promote the development of the edible protein industry and compensate for the gap in protein resources.