来源于玫瑰微球菌的麦芽寡糖基海藻糖水解酶基因在大肠杆菌中的融合表达

Cloning and Expression of Maltooligosyltrehalose Trehalohydrolase in E.coli from Micrococcus roseus QS412

设计引物克隆玫瑰微球菌QS412中麦芽寡糖基海藻糖水解酶(MTHase)的基因treZ,通过与pET-28a(+)载体相连,转化入宿主菌E.coli BL21,进行发酵诱导。通过SDS-PAGE检测到外源基因在大肠杆菌中有很高的MTHase表达量,但大部分都以不溶性包含体形式存在。对菌体超声破碎全菌液检测酶活,结果显示了水解酶酶活。这是来源于微球菌属的麦芽寡糖基海藻糖水解酶首次获得基因克隆和活性表达,为进一步提高酶活、增大海藻糖产量奠定了基础。

A gene encoding the maltooligosyltrehalose trehalohydrolase（MTHase）from Micrococcus roses QS412 was cloned and inserted into pET expression system.Then the gene was expressed in E.coli strain BL21（DE3）.The molecular mass of the recombinant enzyme was estimated to be 68kDa at 8% SDS-PAGE.And also,we studied that the recombinant enzyme can specifically hydrolyzed the maltooligosyltrehalose to release free trehalose,and the enzymatic activity was determined to be 44U/L.