花生四烯酸高产菌M6的鉴定

IDENTIFICATION OF ARACHIDONIC ACID HIGH YIELDING STRAIN M6

为鉴定花生四烯酸高产菌M6考查了M6的形态、生理特征及其核糖体18S rDNA序列。M6菌落为白色,菌落初期很薄,圆形,然后一层层扩展,形成花瓣状,并长出棉花状菌丝。显微镜下观察,菌丝体内有较多的油脂颗粒。菌株M6在4℃低温下和25℃温度下都可以生长,M6菌体油脂的脂肪酸气相色谱分析显示M6可以产生花生四烯酸。M6的18S rDNA的部分序列分析表明其与高山被孢霉同源性最高,达99%。根据M6的形态、生理特征及其核糖体18S rDNA的序列的分析鉴定M6是高山被孢霉。

A strain named M6 which had a high arachidonic acid producing ability was tested for their taxonomic position. The colony of strain M6 was white, thin and round at beginning, and then expanding layer upon layer with rosette patterns and forming cottony hyphae. Oil drops were observed in the mycelia under microscope. Strain M6 had a broad range of growth temperature and could grow at both 4℃ and 25℃. The major fatty acid composition was identified as arachidonic acid by GC. The partial 18S rDNA of M6 was almost 99% identical with that of Mortierella alpina. By morphological and physiological tests, fatty acid composition and 18S rDNA sequence, strain M6 was identified as Mortierella alpina.