Successful biosynthesis of natural antioxidant ergothioneine inSaccharomyces cerevisiaerequired only two genes fromGrifola frondosa

Background Ergothioneine (EGT) has a unique antioxidant ability and diverse beneficial effects on human health. But the content of EGT is very low in its natural producing organisms such asMycobacterium smegmatisand mushrooms. Therefore, it is necessary to highly efficient heterologous production of EGT in food-grade yeasts such asSaccharomyces cerevisiae. Results Two EGT biosynthetic genes were cloned from the mushroomGrifola frondosaand successfully heterologously expressed inSaccharomyces cerevisiaeEC1118 strain in this study. By optimization of the fermentation conditions of the engineered strainS. cerevisiaeEC1118, the 11.80 mg/L of EGT production was obtained. With daily addition of 1% glycerol to the culture medium in the fermentation process, the EGT production of the engineered strainS. cerevisiaeEC1118 can reach up to 20.61 mg/L. Conclusion A successful EGT de novo biosynthetic system ofS. cerevisiaecontaining only two genes from mushroomGrifola frondosawas developed in this study. This system provides promising prospects for the large scales production of EGT for human health.