一株产紫杉醇的南方红豆杉内生真菌的分离及分类研究

从生长在湖北的南方红豆杉树皮中韧皮部分离出一批内生真菌,从中获得一株能产紫杉醇的菌株TPF6。对其形态特征的研究以及生理生化特性的测定(b ilog)结果表明,菌株TPF6与链格孢属有很大的相似性;与18SrDNA分析比对表明,菌株TPF6属于链格孢属,并与链格孢属其他种共享95%~99%的保守序列,其中与交链格孢(Alternaria alternata)18S rDNA的保守度高达99%;全细胞脂肪酸分析结果显示,18:2 CIS9、12/18:0a为TPF6的主要脂肪酸组分,该菌株与链格孢属(Alternaria)相似度最高,SIM值为59.8%。根据分类学研究结果,菌株TPF6属于半知菌门链格孢属,定名为交链格孢(A. alternata)。应用高压液相色谱技术测定结果表明,菌株TPF6发酵液中紫杉醇含量为84.5μg/L。

Taxonomic Study on a Taxol Producing Fungus Isolated from Bark of Taxus chinensis var.mairei

Taxonomic studies were preformed on the strain TPF6,which was isolated from the bark of Taxus chinensis var.mairei growing in Hubei Province.Phenotypic analysis and biolog analysis indicated that strain TPF6 show high similarity with genus Alternaria.Phylogenetic analysis based on 18S rDNA gene sequence indicated that the strain belongs to the genus Alternaria,sequence similarity values with its nearest neighbors are between 95%~99%,and share more than 99% with strain A. alternata.The predominant fatty acid components are 18:2 CIS9,12/18:0a and shares 59.8% the same cellular fatty acid composition with other members in Alternaria.On the base of taxonomic data,the strain was named as A. alternata.The taxol producing ability was determined by HPLC and MS.The result shown that the taxol concentration in fermentation medium is 84.5 μg/L.