灭活原生质体融合选育木糖、葡萄糖共发酵酿酒酵母工程菌

为了选育高效利用木糖、葡萄糖共发酵，并使乙醇产量有所提高的酿酒酵母工程菌株。以酿酒酵母Saccharomyces cerevisiae W5和休哈塔假丝酵母Candida shehatae 20335为亲本株，确定了双亲株原生质体灭活剂量，并进行原生质体融合获得融合子，用高效液相色谱（HPLC）测定融合子以木糖、葡萄糖单碳源及混合碳源发酵时的乙醇得率。结果表明，获得一株发酵性能优良的融合子HDY2-14，其利用木糖和葡萄糖单碳源发酵的乙醇得率分别为0.213g/g和0.257g/g，混合碳源发酵的乙醇得率为0.310g/g，其中混合碳源乙醇得率比亲本株W5和20335的乙醇得率分别提高了20.2%和15.2%。

Breeding of Saccharomyces cerevisiae by inactivated protoplast fusion method for improving ethanol fermentation using xylose and glucose as carbon sources

In order to acquire the Saccharomyces cerevisiae engineering strain for co-fermentation of xylose and glucose mixtures and improving the production of ethanol, the inactivated protoplasts of Saccharomyces cerevisiae W5 and xylose-utilizing Canadida shehatae 20335 were fused. The fusants were selected according to their ability of utilizing xylose and yield of ethanol. The results revealed that the best selected fusant was HDY2-14, which gave the ethanol yield of 0.213g/g, 0.257g/g and 0.310g/g when the xylose, glucose and xylose-glucose mixtures were respectively used as carbon sources. The ethanol production of HDY2-14 from the fermentation of xylose-glucose mixtures was 20.2% and 15.2% respectively higher than that of W5 and 20335.