罗布泊盐湖Halomonas属内种的多样性及系统分类

Identification and Species Diversity of the Genus Halomonas Isolated from Lop Nur Salt Lake

采用4种培养基和常规的分离技术对来自罗布泊盐湖的9份土壤样品进行了分离,结合16S rRNA测序结果采用常规方法对分离菌株进行了鉴定,探索了罗布泊Halomonas属细菌的物种组成情况。实验结果表明:罗布泊盐湖中具有Halomonas属的细菌10个种,其中9个菌株同已知种(Halomonas ventosae Al12T,Halomonas elonga-ta ATCC 33173T,Halomonas caseinilytica JCM 14802T,Halomonas taeanensis KCTC 12284T,Halomonas pantelleriensisDSM 9661T,Halomonas sulfidaeris DSM 15722T,Halomonas salina F8-11T和Halomonas cupida DSM 4740T)的相似性在98.4%～100%之间;另外,获得1个菌株(编号为GT 123),同关系最近的模式种Halomonas anticariensis的相似性仅为95%,属于Halomonas属内一个新的分支。菌株GT 123的多相分类结果表明其分类地位为Halomonas属内的一个新种。由此可见,罗布泊盐湖存在丰富的Halomonas属细菌物种多样性,并且潜藏着一定的新物种资源。

Phylogenetic diversity of the strains in the genus Halomonas from hypersaline environments in Lop Nur region was inves-tigated using traditional culture - dependent method and 16S rRNA phylogenetic analysis. Total nine strains isolates exhibited the clo-sest phylogenetic affinity and highest sequence similarity （98.4%-100% ） to Halomonas ventosae, Halomonas elongata, Halomonas caseinilytica , Halomonas caseinilytica , Halomonas taeanensis , Halomonas pantelleriensis , Halomonas sulfidaeris , Halornonas salina and Halomonas cupida, respectively.. In addition, a novel bacterium, GT 123, was isolated from a salt lake Luobupo. The affiliation of strain GT 123 with the genus Halomonas was confirmed by 16S rRNA gene sequence comparisons. The most closely related species was Halomonas anticariensis, which showed a 16S rRNA gene sequence similarity of 95%. On the basis of the data from this polyphasic study, strain GT 123 represented a novel species of the genus Halomonas. The results indicated that there was not only abundant phylo-genetic diversity of the genus Halomonas, but also some unknown bacterial groups existed in hypersaline environments in Lop Nur re-gion.