原生质体融合构建直接转化淀粉生产燃料酒精的新型菌株

Construction of New-type Fusants(Which Transformed Starch Directly into Fuel Alcohol) by Protoplast Fusion

以K氏酵母、糖化酵母为亲本,采用单亲灭活原生质体融合技术进行属间融合,构建可直接转化淀粉产酒精的菌株。结果表明,取培养6～8 h的单倍体,在30℃下,用2.0%的蜗牛酶酶解1 h,均可获得高于92%的形成率及6.5%的再生率,制备好的原生质体经紫外线灭活糖化酵母后融合频率为7.3×10-6;最终获得一株性状稳定、酒精转化率高的融合子,在含5.0%的可溶性淀粉发酵液中,酒度可达7.0%(v/v)。

S.cerevisiae K and S.diastaticus were used as parent strains to construct a new strain （which could directly transform starch into fuel alcohol） by inactivating S.diastaticus through protoplast fusion. The process was as follows： haploidy cultured for 6-8 h and then enzymolysis of haploidy for 1 h at 30℃ by using 2.0 % snaillase, and the formation rate and the regeneration rate reached 92.0 % and 6.5 % at least, and the fusion frequency of prepared protoplast was 7.3 ×10^-6 through inactivating S.diastaticus by UV, then the new-type fusants of stable properties and high alcohol transformation rate were produced eventually, which could produce 7.0 %（v/v） alcohol in 5.0 % soluble starch fermenting medium.