黄芪毛状根淀粉粒结合淀粉合成酶(GBSS)基因表达载体的构建及在大肠杆菌中的表达

Establishment of Genetic Expression Carrier of Starch Grain Bi nding Amylosynthetase(GBSS) in Hairy Roots of Radix Astragali Expression in Bacillus Coli

以膜荚黄芪毛状根中克隆得到的GBSS基因序列设计一对特殊引物 ,得到了包含GBSS基因全部表达序列的1.9kb的cDNA片段。该片段正向连接于切除了GUS基因的pBI12 1上 ,构建成表达载体pBI-gbss。SDS -PAGE实验证实了GBSS基因在含有该表达载体的DH5α的大肠杆菌中得到表达。酶活性测定表明转化菌株比未转化菌株高出 2 0 %。

By designing a pair of specific inducers with GBSS genetic series obtained from cloned hairy roots of Astragalus membranaceus(Fisch.)Bung,cDNA fragment of 1.9kb including the total genetic expression series of GBSS was obtained.This fragment was positively linked to pBII21 with GUS cut off,to establish an expression carrier,pBI-gbss.SDS-PACE experiment has proved that GBSS gene was expressed in Bacillus Coli of DH5α containing this expression carrier.The enzymatic activity determination indicated that transformed strain was 20% higher than nontransformed strain.