[Actinobacterial diversity in sediments of Ebinur lake, Xinjiang, China]

Abstract

Objective: The goal of this study was to identify uncultured actinobacterial diversity in Xinjiang Ebinur salt lake sediment.

Methods: Total DNA was extracted from 5 sediments of Ebinur lake and the actinobacterial 16S rRNA gene clone libraries were constructed through touchdown PCR program with the common primers. White clones were randomly selected after blue-white spot screening and detected by PCR. Positive clones were analyzed by restriction fragment length polymorphism (RFLP) with restriction enzyme Hha Ⅰ, and clones with unique RFLP were selected to analyze their sequences. After Chimera Check analysis, the sequence homology was analyzed by BLAST and phylogenetic tree was constructed by MEGA 5.0 software.

Results: In total 192 white clones were randomly selected and 166 clones were positive clones. The sequences of 51 clones with unique RFLP were analyzed and detected with Check Chimera program. The results show that 36 OTUs were obtained and GenBank accession numbers were KR182090-KR182131. The library coverage C value was 90.4% and 36 OTUs could be divided into 2 clusters by phylogenetic analysis. The first cluster accounted for 18.1% of the library and belonged to one class Actinobacteria of phylum Actinobacteria, which contained 4 orders including Actinomycetales, Propionibacteriales, Micrococcales and Corynebacteriales. Another cluster was the unclassified actinobacteria, divided into 3 groups and accounted for 81.9% of the library.

Conclusion: Ebinur Lake has a lot of unknown actinobacteria that need to be further investigated.