高耐性酿酒酵母的杂交育种

Construction of S.cerevisiae with Good Osmo-tolerance and High Ethanol-production Characteristic

利用不同特性的酿酒酵母AY-15,M1进行生孢培养和孢子分离试验,得到185株产酒、153株耐渗单倍体。其接合型,a型约占1/4,α型占约1/2,其余为不确定株。经筛选试验后得到13株产酒性能良好的单倍体和19株耐渗性能良好的单倍体。利用酒精发酵试验进行复筛,得到两株性能最优良的单倍体,作为杂交试验的亲本。杂交试验后,经耐渗、耐酒精杜氏管试验和发酵性能测定,得到一株能够在高渗环境中仍然保持较高产酒精能力的酿酒酵母,在含盐5%的培养基中发酵产酒精能力分别比AY-15,M1提高19.6%和15.4%。

185 high ethanol-production haploids and 153 good osmo-tolerant haploids were obtained through spore separation test and spore culture ofS.cerevisiae AY-15 and M1 of different properties. Among all the mating types, a type accounted for about 1/4, a type accounted for about 1/2, and others were uncertain strains. By measuring the endurance of yeast haploids, 13 high ethanol-production haploids and 19 good osmo-tolerant haploids were selected. Alter the fermentation, two haploids were selected as the parents for the hybridization. 236 diploid strains were constructed by crossing the parents. At last, one strain was obtained through the measurement of their osmo-tolerance capacity and fermenting power and alcohol-resistant test, which could maintain high ethanol-production capacity under hyperosmotic environments. Its ethanol-production capacity in culture medium containing 15 % salt increased by 19.6 % than AY-15 and by 15.4% than M1 respectively.