拟诺卡氏菌16S rRNA,gyrB,sod和rpoB基因的系统发育分析

为了更好地了解拟诺卡氏菌属(Nocardiopsis)各物种间的系统发育关系,该属现有有效描述种的gyrB,sod和rpoB基因的部分序列被测定,结合16S rRNA基因,对拟诺卡氏菌属进行了系统发育重建。研究发现拟诺卡氏菌属gyrB,sod和rpoB基因的平均相似性分别为87.7%、87.3%和94.1%,而16S rRNA基因的平均相似性则达到96.65%,3个看家基因均比16S rRNA具有更高的分歧度。比较基于不同基因的系统树发现,由gyrB基因得到的系统树拓扑结构与16S rRNA得到的结构在亚群上基本一致。因此,gyrB基因在拟诺卡氏菌属的系统分类上比16S rRNA基因更具优越性。

Phylogenetic analysis of Nocardiopsis species based on 16S rRNA,gyrB,sod and rpoB gene sequences

In order to understand the phylogenetie relationships among Nocardiopsis species more rationally, the gyrB, sod and rpoB gene partial sequences of 24 validly published Nocardiopsis species were determined. The phylogenetic trees were reconstructed including 16S rRNA gene and above-mentioned three housekeeping genes. The average similarities of gyrB, sod and rpoB of Nocardiopsis species were 87.7% ,87.3 % and 94.1%, respectively. Meanwhile, the average similarity of 16S rRNA gene of Nocardiopsis species was 96.65%. The variabilities of gyrB, sod and rpoB gene in Nocardiospis are greater than that of 16S rRNA gene. By comparing the phylogenetic trees, the topology of gyrB gene tree is almost consistent with that of 16S rRNA gene tree. Consequently, the gyrB gene possesses the superiority in phylogenetic taxonomy of the genus Nocardiopsis.