人微小纤溶酶原基因的克隆和表达

Construction and Expression of Human Micro Plasminogen Gene in Escherichia coli

用ＰＣＲ方法扩增人微小纤溶酶原（Ｍｉｃｒｏｐｌａｓｍｉｎｇｅｎ，ｍＰｌｇ）基因，再与表达载体重组，构造ｍＰｌｇ原核表达质粒并转化大肠杆菌。阳性克隆ｐＳＳＥｍＰｌｇ经温度诱导表达，ＳＤＳＰＡＧＥ等方法证明表达产物的分子量约为２９ｋＤａ，占全菌总蛋白的２４％左右，并在菌内形成包涵体。经半胱氨酸再氧化法和空气氧化法复性，表达产物ｒｍＰｌｇ经ＳＫ作用后显示纤溶活性。同时对蛋白质浓度。

Human mPlg was amplified by PCR, using pBS S1 cDNA encoding human plasmingen as a templete. The mPlg gene was cloned into expression vector and transfected into E.coli JF1125. SDS PAGE analysis revealed that expression product was Mr.29 and about 24% of total bacteria protein and formed inclusion body. After refoding by Air Oxidation and Cysteine Reoxidation, the fibrinolysis activity of r mPlg was shown. Effects of protein concentration and refolding time on renaturation efficiency were discuss.