【摘要】 以噬菌体λEMBL3为载体,大肠杆菌Q358,Q359为宿主构建了地衣芽胞杆菌的基因文库,用I₂-KI染色法从该文库中分离出α-淀粉酶基因,并将含该基因的2.5kb片段亚克隆至pBR322。限制图谱分析显示克隆的基因与国外克隆的地衣芽胞杆菌基因有所不同。将2.5kb的基因片段与质粒pUB18的BamHI片段连接、组建重组质粒pUA44,并将其转入枯草杆菌的感受态细胞及短小芽胞杆菌的原生质体,实验结果证明,克隆基因可在枯草杆菌及短小芽胞杆菌中表达。更多还原

【Abstract】 The gene coding for the a-amylase gene from Bacillus licheniformis 802 has been isolated from a genomic library in E. coli using the bacteriophage γ EMBL3 as a vector. The 2.5kb BamHI fragment containing the α-amylase gene has been subcloned in pBR322 and its restriction map determined, which shows a little difference with the gene cloned by Sibakov and Joyet groups. In the new clone, called pAM20, the α-amylase was shown to accumulate in the cell. The 2.5kb BamHI fragment was ligated with BamHI digested pUB18 and the resultant plasmid pUA44 was tramformed into B. subtilis and B. pumilus by competent cell and protonlast tramformation and the expression of the gene has been examined.更多还原