摘要
本实验从构建于大肠杆菌DH5α的瑞氏木霉cDNA文库中用PCR法体外扩增到木聚糖酶Ⅰ(XynⅠ )的DNA片段 ,然后连接至穿梭载体pAJ40 1 ,转化酵母H1 58.以刚果红染色法筛选阳性重组子并测序 .当将其mRNA5’端非翻译区的 79个碱基删除后 ,木聚糖酶的表达水平显著提高 .有可能此基因的调节区位于5’端非翻译区内 。
The Xylanase I (XynI)DNA fragment was amplified in vitro by PCR from Trichoderma reesei cDNA bank constructed in Escherichia coli DH5α.The XynI DNA fragment was then inserted in the recombinant plasmid pAJ401 and introduced into S.Cerevisiae .The positive clones were isolated by Congo red-staining method and didexoxynucleotide method was used to sequence the XynI DNA fragment.After deletion of 79 bases in 5' untranslated region from XynI mRNA,the XynI expression level increases greatly which suggests that the regulation region could exist in the 5' untranslated region of XynI mRNA and could be recognized by the gene expression related factors of S.Cerevisiae .
