【摘要】 利用已克隆的透明颤菌(Vitreoscilla)血红蛋白基因(vgb),构建了一批复制类型和抗生标记不同的vgb表达载体,并就vgb基因表达及其对几种基因工程大肠杆菌的影响进行了初步研究。实验证明vgb基因的表达具有氧调控特性,在溶氧水平下跌至20％饱和度时迅速合成。vgb基因的表达产物(Vitreoscilla Hemoglogin,VHb)可促进青霉素酰化酶和TNF、IL-2等基因工程菌在低氧条件下细胞生长和产物表达的状况,由于vgb基因的表达降低了细胞对氧的敏感程度,可望运用它来改善发酵过程中溶氧控制裕度。这些实验结果预示着vgb基因在耗氧生物过程中,如抗生素工业和基因工程菌高密度发酵,有着良好的应用前景。更多还原

【Abstract】 A series of expression vectors of Vitreoscilla hemoglobin gene (vgb) has been con.structed with different replication origins and resistance. The expression of vgb and its effects on several recombinant strains were studied. The results verify that the expression of vgb was regulated by the level of dissolved oxygen (DO), which increased repidly as DO dropped below 20% of its saturation. The expressed Vitreoscilla hemoglobin (VHb) in engineered Escherichia cole of IL-2, TNF and penicillin acylase could improve the cell growth and desired products in the oxygen-limited condition. It also showed that the DO control of fermentation could become easier due to the lower sensitivity to oxygen of the cells with vgb expressed and suggested that vgb could be further applied in the oxygen-limited bioprocesses.更多还原