被孢霉△~9脂肪酸脱饱和酶基因保守区的cDNA克隆及结构分析

被孢霉被广泛采用用于发酵生产γ-亚麻酸、花生四烯酸和EPA等多不饱和脂肪酸。为了解决发酵产率过低等诸多问题，我们拟采用基因工程技术改造生产菌株。通过对已克隆△~9脂肪酸脱饱和酶基因的分析，合成一组简并引物，PCR扩增了被饱霉△9脂肪酸脱饱和酶基因的保守区。结果表明被抱霉△9脂肪酸脱饱和酶基因保守区由537个核苷酸组成，共编码179个氨基酸。其与迄今为止发表的微生物面△9脂肪酸脱饱和酶基因有很高的同源性。这是被饱霉△~9脂肪酸脱饱和酶基因研究的次次报道。

CLONING AND STRUCTURE ANALYSIS OF THE CONSERVED REGION OF △~9 FATTY ACID DESATURASE GENE FROM MORTIERELLA

Morlierella species are the main fungi producing polyunsatUated fatty acid(PUFA), including γ-lindenic acid； Arachidonic acid and EPA. A strain of Mortierella sp. was reformed by genehc engineering for the purpose of solving some problems ocurring in fermentation. Conserved region of △9 fatty acid desaturase gene from Mortierella was cloned and sequenced through PCR using one group of degenerate primers designed on the basis of analysis of cloned A' fatty acid desaturase Sequences. Results show it consistS of 531 nucleohdes encoding 179 axnino acids in all and has very high homolgy to previously cloned △9 fatty acid desaturase in the field of Microbe. This is the first time that A9 fatty acid desaturase gene from Mortierella was cloned.