摘要
以扣囊复膜孢酵母菌总DNA为模板, 通过PCR扩增克隆到约1.5kb的α-淀粉酶基因(AMY)。用酵母菌穿梭载体YEp352为出发质粒,磷酸甘油酸激酶基因1(PGK1)启动子和乙醇脱氢酶基因1(ADH1)终止子为调控元件构建了含α-淀粉酶基因编码序列的酵母菌重组表达质粒pLA8。pLA8导入工业啤酒酵母菌,在以淀粉为唯一碳源的YNBS培养基上筛选阳性转化子,转化子培养液中α-淀粉酶活性为1.1U/ml,细胞破碎液的酶活性为0.3U/ml,而受体菌培养液及细胞破碎液中未检测到α-淀粉酶活性。
A 1.5kb α-amylase gene was prepared by PCR with Saccharomycopsis fibuligera genomic DNA as the template.The gene, together with phosphoglycerate kinase1 promoter and ethanol dehydrogenase1 terminator from S. cerevisiae was clonedinto a yeast expression vector (YEp352), generating a recombinant plasmid pLA8. The recombinant plasmid was introduced intoS. cerevisiae and the transformants were screened on the medium in which starch was the sole carbon source. The average α-amylase activities of the transformants in cellular extract and culture supernatants were 0.3U/ml and 1.1U/ml respectively. Noα-amylase activity was detected in those of the host strain.
出处
《食品科学》
EI
CAS
CSCD
北大核心
2004年第9期78-82,共5页
Food Science
