羟酸还原异构酶基因在啤酒工业酵母中的整合表达

Study on the Integrative Expression of ILV5 Gene in Brewer′s Yeast

采用PCR技术扩增啤酒工业酵母QY中的羟酸还原异构酶基因ILV5,构建了整合载体YIp 5C,整合转化QY,通过铜抗性筛选转化子,所得的转化子的羟酸还原异构酶的活力明显高于对照菌株QY,转化子产生的双乙酰的量比原始菌株降低了40%.

The ILV5 gene encoded reductoisomerase was amplified by Polymerase Chain Reaction from brewer's yeast QY. The 2.6 kb amplified product, 0.43 kb CUP1 fragment and 0.9 kb MTI fragment were inserted into YIp5 to form recombinant plasmid YIp5C. Stable brewer's yeast transformants were obtained by integration of YIp5C into chromosome. In beer fermentation, the transformant showed a 40 % reduction in diacetyl formation compared to that of the control yeast QY.