大肠杆菌腺苷脱氨酶基因的克隆表达

Cloning and Expression of E. coli Adenosine Deaminase Gene

将大肠杆菌K12菌株来源的腺苷脱氨酶基因(add)克隆到载体pET-28a中,并转化至大肠杆菌BL21(DE3)中进行表达。通过IPTG诱导,SDS-PAGE检测和酶活性的测定发现,重组菌表达产生大量腺苷脱氨酶,活性达到51.07U/mg蛋白。通过酶性质的研究,腺苷脱氨酶对腺苷最适pH和温度分别为7.5和40℃,且在40℃下维持稳定。

The gene encoding adenosine deaminase（add）from Escherichia coli K12 was cloned into expression vector pET-28a and transformed into the strain E. coli BL21 （DE3）. The protein was highly expressed after the induction with IPTG,then was analyzed with SDS-PAGE and confirmed by the assay of activity. The activity of adenosine deaminase expressed could reached up to 51.07 U/mg protein. The study of characterization showed that adenosine deaminase had optimum pH 7.5 and optimum temperature at 40℃ with thermal stability at 40℃.