扣囊复膜孢酵母b-葡萄糖苷酶基因在工业酿酒酵母中的表达

本文以工业酿酒酵母菌株( Saccharomyces cerevisiae Y )为研究对象，针对其复杂的生理生化遗传特性，建立了相对应的转化体系。以pRS41H质粒为基础载体，构建了含有工业酿酒酵母自身的gpd2启动子、终止子和扣囊复膜孢酵母的b-葡萄糖苷酶基因bgl的重组质粒pRS-gb。电击转化进入工业酿酒酵母细胞，潮霉素抗性筛选，获得重组菌。该重组菌可以在以纤维二糖为唯一碳源的培养基中生长，培养36 h，b-葡萄糖苷酶酶活达到0.967 u/ml。以纤维二糖为唯一碳源的酒精发酵中，酒精度可以达到0.92 g/l。这对工业生产中利用纤维素为原料发酵生产酒精具有重要意义。

Expression of bgl gene from Saccharomycopsis fibuligera in industrial Saccharomyces cerevisiae

According to complex physiological and biochemical genetic characteristics of industrial Saccharomyces cerevisiae Y, a corresponding transforming system was built primarily. It is essential for improving yeast strain by metabolic engineering. The recombinant plasmid, which contains gpd2 promotor and terminator from industrial Saccharomyces cerevisiae Y and β-Glucosidase gene (bgl) from Saccharomycopsis fibuligera, and uses Plasmid pRS41H as shuttling expression vector, was successfully transformed into industrial Saccharomyces cerevisiae Y. The recombined yeast can grow on the medium of cellobiose as sole carbon source. The highest enzyme activity achieved 0.967 u/ml, at 36 h, and the ethanol concentration was 0.92 g/l when fermenting cellobiose as sole carbon source，which is higher than fermenting by industrial Saccharomyces cerevisiae Y.