扣囊复膜孢酵母BGL1基因在工业酒精酵母中的整合表达

Integration and Expression of BGL1 Gene from Saccharomycopsis fibuligera in Industrial Saccharomyces cerevisiae

摘要:

构建了含有工业酿酒酵母自身GPD2启动子和终止子、扣囊复膜孢酵母b-葡萄糖苷酶基因(BGL1)和潮霉素选择性标记hyg的重组质粒pPIC-gpd-bgl-hyg, 通过酵母染色体同源重组, 将BGL1基因整合进入工业酒精酵母的染色体上。重组酵母可以在以纤维二糖为唯一碳源的培养基上生长, 48 h时b-葡萄糖苷酶酶活达到0.764 U/mL。在玉米浓醪酒精发酵实验中, 与宿主菌株相比, 重组酵母醪液中纤维二糖含量减少约80％, 达到了消耗醪液中纤维二糖含量的目的。

Abstract:

The recombinant plasmid pPIC-gpd-bgl-hyg was constructed, which contained GPD2 promotor and terminator from industrial yeasts Saccharomyces cerevisiae, b-glucosidase gene (BGL1) from Saccharomycopsis fibuligera and hyg from hygromycin as the selected marker. With the yeast’s high efficiency of homologous integrated, the BGL1 gene was successfully integrated into industrial yeasts S. cerevisiae. The recombined yeast could grow on the cultures with the cellobiose as a sole carbon source, and the β-glucosidase activity achieved 0.764 U/mL after 48 hours’ cultivation. In the experiments of VHG ethanol fermentation, the cellobiose concentration in broth of recombined yeast was 80% lower than that of industrial yeast.