絮凝性强及熟化期短的啤酒酵母工程菌的研究

In this study, a DNA fragmemt carrying FLO gene from S.cerevisiae FL189 which displayed strong flocculence was cloned. screened. The result of sequencing showed that: the cloned DNA fragment is 4396bp in size with a 3936bp ORF, which is 99% homologous to FLO1, so designated as FLO1G. The differences of FLO1G and FLO1 are as follow: In the ORF of FLO1G , a 675bp fragment was missing. The putative TATA box at -235 and CAAT box at -296, which in the flanking region of FLO1 were not found in FLO1G. Compared with FLO1, there are five different bases in FLO1G. FLO1G was cloned into the constructed pCF1, which contained PGK1 promoter, PGK1 terminator,CUP1 gene. pCF1 was introduced into indurastria yeast strain PJ208-5, which carrying ALDC gene and sensitive to Cu2+.The results showed that the transformants poss strong flocculation ability. The transformants showed about 40% reduction in diacetyl fomation compared to the PJ208-5 strain in fermentation tests. This study can not only make it more practical for industrial use, but also provide more evidence to clarify the mechanism of flocculation.

增强絮凝性、缩短熟化期、简化后处理工艺是国内外啤酒工业亟待解决的重要问题。本项目拟将絮凝基因(FLO)引入已构建的含有乙酰乳酸脱羧酶基因(ALDC)啤酒酵母新品系，构建絮郧俊⑹旎诙獭⒈３衷蟹缥丁⒈阌诤蟠淼钠【平湍腹こ叹Ｎ钊胙芯啃跄肿踊淼於ɑ。晃ひ稻指牧继峁├砺垡谰莺涂尚型揪丁＞哂兄匾砺垡庖搴凸惴河τ们熬啊