【摘要】 重组人组织型纤溶酶原激活物衍生物（Ｋ２Ｐ）体内半衰期长优于天然ｔＰＡ。在原核系统中直接表达Ｋ２Ｐ的表达量很低，仅５％左右，构建Ｔｒｘ－Ｋ２Ｐ融合蛋白后可将表达量提高至１０％。为了进一步提高产量，使用诱导剂（ＩＰＴＧ）作为选择压力对重组菌株进行培养和筛选，获得了变异的宿主菌，有效地提高了融合蛋白在大肠杆菌Ｔ７启动子系统中的表达，诱导５ｈ后表达量达到了２８．８％。同时宿主菌获得了对诱导剂的耐受性，能在诱导后持续生长，最终增加了目的蛋白的产量。更多还原

【Abstract】 The derivative of recombinant human tissue-type plasminogen activator K2P is the preferred thrombolytic drug. The expression level was very low when K2P expressed directly in prokaryotic system, only 5% . After Trx-K2P fusion protein constructed, the expression level was raised to 10% . In order to ob-tain high level production, the mutant host was screened out after incubated with 0.7mmol/L IPTG. The ex-pression of fusion protein in E. coli T7 promoter system was enhanced effectively, and reached 28.8% 5 hours after induction. The host strain simultaneously attained the ability to endure IPTG. The bacteria grew stably after induction. The quantity of target protein was increased vigorously.更多还原