深黄被孢霉△5-脱饱和酶基因在花生四烯酸合成中的作用

Effect of Mortierlla isabellina △5-desaturases gene on arachidonic acid synthesis

【目的】研究△5-脱饱和酶基因的mRNA表达量与花生四烯酸产量之间的关系。【方法】实验利用荧光定量PCR方法检测了△5-脱饱和酶在五株深黄被孢霉的同一培养时间及菌株YZ-124在不同发酵阶段的mRNA表达水平,同时利用气相色谱仪测定其花生四烯酸含量。【结果】结果表明:不同菌株的△5-脱饱和酶基因的mRNA表达水平不同,原始菌株As3.3410最低,诱变菌株YZ-124最高;深黄被孢霉YZ-124不同发酵阶段的△5-脱饱和酶基因mRNA表达量随菌龄的增加逐渐增加。【结论】结合ARA的得率显示,△5-脱饱和酶基因mRNA表达量与培养物油脂中ARA含量呈一定的正相关关系。

[Objective]To study the relation between mRNA expression of △5-desaturase gene and arachidonic acid production. [Methods ] Using fluorescence quantitative PCR,we determined the mRNA expression levels of △5-desaturase gene of five Mortierlla isabellina strains cultured for the same time and strain YZ-124 cultured for different time. Simultaneously,we measured the contents of arachidonic acid by gas chromatography. [Results] The results showed that △5-desaturase gene mRNA expression level of distinct strains was different. Expression level of the original strain As3. 3410 was the lowest,whereas that of the mutant strain YZ-124 was the highest. The mRNA expression of △5-desaturases gene decreased gradually with fermentation time. [Conclusion]According to arachidonic acid yield,mRNA expression quantity of △5-desaturase gene presented a positive correlation with arachidonic acid content in cultured oil.