Endogenesis Expression of Sterol C-24 Methyltransferase Increases Ergosterol Biosynthesis in Saccharomyces cerevisiae
甾醇C-24甲基转移酶基因在酿酒酵母中的内源表达及工程菌麦角甾醇的合成

Ergosterol is economically important as the precursor of vitamin D2 and the main material to produce steroid drugs. The biosynthesis of sterols in yeast is complex. ERG6 gene encodes the sterol C-24 methyltransferase catalyzing the fifteenth reaction in ergosterol biosynthesis. In this study, ERG6 gene was cloned from Saccharomyces cerevisiae YSF-20 by PCR. To express ERG6 gene properly in S. cerevisiae, expression plasmid pPERG6 containing ERG6 under the control of PGK1 promoter was constructed and then introduced into S. cerevisiae YS58 to generate recombinant strain YS58(pPERG6). Results of ERG6 disruption and complementation showed that the ERG6 gene on plasmid pPERG6 expressed functionally in S. cerevisiae. The ergosterol content in recombinant strains YS58(pPERG6) was 1.32 times of that in the control strain YS58(YEp352), and at the same time, the biomass of the recombinant strain was 1.23 times of that of the control strain. Results in this study showed that the internal expression of ERG6 gene enhanced the ergosterol biosynthesis in yeast.