一种新的耐热性植酸酶基因在烟草中的表达

Expression of a New Heat-resistant Phytase Gene in Tobacco

[目的]探究一种新的耐热性植酸酶基因在烟草中的表达结果。[方法]克隆了泡盛曲霉植酸酶基因编码区全序列,使其在烟草中高效表达,对重组植酸酶与天然植酸酶性质进行初步的分析和比较。[结果]对烟草叶片的植酸酶活性检测结果表明,重组植酸酶基因在烟草中得到较高水平表达,转基因植株的最高植酸酶活力为对照烟草的13倍;对烟草重组植酸酶蛋白的酶学性质进行了初步分析,结果表明重组植酸酶拥有与天然植酸酶同样的最适pH值和最适温度,耐热性略微下降,但在80℃处理15 min后仍有33%的残余酶活力。[结论]该研究为该植酸酶基因转化饲料作物的开发提供理论依据,也为泡盛曲霉植酸酶的工业化生产开辟了新的途径。

[Objective] The aim was to research the expression results of a new heat-resistant phytase gene in tobaeco. [Methed] The primary analysis and comparison were conducted on the properties of recombinant phytase and natural phytase by cloning phytase gene eeding ,sequence of AspergiUus awamori and making it expressed highly efficiently in tobacco. [ Result] The results of phytase aetivity detection of tobacco leaves showed that the recombinant phytase gene obtained expression with higher level in tobacco and the highest phytase activity in transgenie plant was 13 fold of that in the eontml tobaeeo. The results of primary analysis on the enzyme properties of recombinant phytase in tobacco showed that the recombinant phytase possessed the same optimum pH and optimum temperature with natural phytase. Though its heat-resistance decreased a little, it also had 33% of the residual enzyme activity after treating the reeombinant phytase at 80 ℃for 15 min. [Conelusion] The research not only provided theoretical basis for the development of forage crops transformed by the phytase gene, but also opened up a new way for industrial preduetion of phytase in Aspergillus awamori.