Western blot analysis showed that rhpk - 5 ( recombinant human plasminogen kringle 5 , rhpk - 5 ) protein was recognized by mab same as native hpk - 5 . the result suggested that we obtained correct gene sequence of hpk - 5 and got the purified rhpk - 5 . section ii : construction of pbv220 / hpk - 5 vector for obtaining high - level hpk - 5 expression system , the hpk - 5 gene was recombined with plasmid pbv220 to construct the vector of pbv / hpk - 5 Coli )作為宿主,經(jīng)sds - page分析,篩選表達量最高的菌株作為發(fā)酵用工程菌株;用western - blot方法鑒定hpk - 5因子的免疫學活性;用搖瓶發(fā)酵的方法,研究發(fā)酵培養(yǎng)基的體積(溶解氧) 、組成成份及誘導起始時間和誘導持續(xù)時間對目的蛋白表達量的影響,優(yōu)化hpk - 5基因工程菌的表達條件。