一株蓝藻内生真菌的鉴定及其产物抑菌活性

Identification of endophytic fungus of cyanobacteria and antimicrobial activity test of its products

从色球藻(蓝藻)的原生质体中分离出一株内生真菌DT06。形态学鉴定结果表明该真菌属于头孢属Cephalosporium,ITS测序结果显示该菌株与Si mplicilliumlanosoniveum(=Cephalosporiumlanosoniveum)的同源性为98%,但菌株DT06的分生孢子及菌落颜色与S.lanosoniveum不同,因此DT06是S.lanosoniveum的变种,定名为Si mplicilliumlanosoniveumvar.tianjinienss Q.L.Dong。模式标本保存在中国科学院微生物研究所菌物标本馆(HMAS)。活体模式菌种保藏在中国普通微生物菌种保藏中心(CGMCC)。进一步的实验结果表明:该真菌能产生对革兰阳性细菌有很强抑制作用的活性物质,并且该物质的合成与细胞生长部分偶联,沙保培养基有利于其抑菌物质的合成。

An endophytic fungus DT06 was isolated from Chroococcus（a genus of cyanobacteria）.Morphological identification indicated that strain DT06 belonged to Cephalosporium genus,and the phylogenetic analysis of ITS sequence of DT06 revealed that it was closely related to that of Simplicillium lanosoniveum（=Cephalosporium lanosoniveum）,with 98% sequence homology.Whereas,the conidia and colony color of DT06 were quite different from those of the model strain.These results suggested that strain DT06 was a variation species of S.lanosoniveum,and we named it as Simplicillium lanosoniveum var.tianjinienss Q.L.Dong.The holotype specimen was kept in Herbarium Mycologicum Academiae Sinicae（HMAS）,Beijing.And living culture of strain DT06 is deposited in CGMCC.Further test results demonstrated that strain DT06 produced bioactive metabolites（with the highest yield on Sabouraud＇s medium）,exhibiting strong antimicrobial activity against Gram positive bacteria,and the biosynthesis of which was partly associated with cell growth.