Phylogenetic Diversity of Halophilic Actinomycetes from Hypersaline Environments in Tarim Basin of Xinjiang, China

Abstract:

Phylogenetic diversity of halophilic actinomycetes from hypersaline environments in Tarim basin was investigated by using culture-dependent method and phylogenetic analysis based on 16S rRNA gene sequences. The results showed that the eighteen isolates, which were isolated from different hypersaline soil samples isolates belongs to three different families(Glycomycetaceae, Pseudonocardineae and Nocardiopsaceae) of the order Actinomycetales, and the most abundant and diverse isolates were within the Actinopolyspora(38.9%), Nocardiopsis(27.8%) and Streptomonospora(22.2%). In addition, four of the five known genera isolates were obtained for those halophilic Actinomycetes. Interestingly, strain YIM 92370 formed one distinct clade in phylogenetic tree based on 16S rRNA gene sequences among the family Glycomycetaceae, and it was noted that strain YIM 92370 is phylogenetically nearest to the genera Glycomyces and Stackebrandtia, but apparently is not a member of the two known genera or any of the other currently described actinomycetal genera. So it is proposed that the strain represents a new genus within the family Glycomycetaceae with 92% sequence similarity with the described species of this family. The results indicated that there was not only abundant phylogenetic diversity of halophilic actinomycetes, but also some unknown actionobacterial groups existed in hypersaline environments in Tarim basin.