大肠杆菌表达的人血管内皮细胞生长因子的复性与纯化研究

以包涵体的形式在大肠杆菌中表达人血管内皮细胞生长因子（VEGF121），采用发酵罐进行工程菌的高密度发酵，得到菌干重46g／L，VEGF121包涵体4．5g／L。包涵体经洗涤、溶解、超滤法复性，得率为81％。复性后的目标蛋白经离子交换色谱及SepharcryS-100凝胶过滤色谱纯化，目标蛋白的纯度达到95％，目标蛋白的总得率31％。采用该工艺制备的VEGF121能刺激人脐静脉血管内皮细胞增殖，具有天然VEGF生物学活性。

Refolding and purification of recombinant human VEGF-121 expressed as inclusion bodies in Escherichia coli

Vascular endothelial growth factor 121 (VEGF121) was expressed as inclusion bodies by recombinant Escherichia coli. High concentrations of both biomass (46 g dry cell/L) and VEGF121 inclusion bodies (4.5 g/L) were obtained by applying a high-cell-density culture. After the inclusion bodies were washed and dissolved, VEGF121 was refolded at 0.2 mg/ml by ultrafiltration in refolding buffer with a yield of 81%. Renatured VEGF121 was purified by anion chromatography and Sephacry S-100 chromatography with purity higher than 95% and fnal purification yield of 31%. The purified VEGF121 could stimulate the proliferation of human umbilical vein endothelial cells as demonstrated by a biological activity assay.