Diversity Of Halophilic Bacteria In Xinjiang Two Salt Lakes Using An Integrated Approach Of BIOLOG Carbon Source Screening And Culture-Dependent Methods

There are various kinds of saline environments on the earth, which have formednaturally or artificially. Due to the environmental specificity, the life forms in thesehabitats are mainly composed of halophilic bacteria. As a noval prospective microbialresource, Halophilic bacteria not only have a very special feature in physiologicalstructure and metabolism, but also can generate many bioactive substances withspecial properties, which has been a hot spot issue of microorganism in extremeenvironment.In this article, BIOLOG method were use to screened the carbon sources whichare easy to use by bacteria, and then added these carbon sources into the separationmedia to isolate halophilic bacteria in Hami Nanhu and Aydingkol Lake, Xinjiang.Bacterial16S rRNA gene universal primers (27F/1492R) were employed for PCRamplification; sequencing and BLAST alignment to identify the strains select thesequences with high similarities which have been published. Using Mega4.0softwareand neighbor-joining method to built16S rRNA gene phylogenetic tree to analysis itsphylogenetic classification and determine the taxonomic status of these isolatespreliminarily, obtain the information of halophilic bacteria diversity. So that we canintroduce a fast and feasible method to design separation medium about carbonsource.The results of Xinjiang Hami Nanhu study showed that the BIOLOG methodscreed five kinds of carbon sources were trehalose, sucrose, citric acid, glycerol andmannitol respectively. There are66isolates from Hami Nanhu soil sample whichwere isolated from the filter carbon sources that added to the separation medium andthey belong to14genera,7families,3phylum via molecular biology identification.Among them35isolates were Firmicutes bacteria and is the most advantage (53%),and the most dominant strains belongs to Bacillus and Sediminibacillus genus;followed by Actinobacteria22strains (33.3%), the dominant genera areNocardiopsis and Streptomyces; Proteobacteria strains (13.7%), all belong to theHalomonas genus. These66strains classified in27OTU,6strains in the27 representative strains16s rRNA gene sequences homology with the nearest speciesare94.24%to96.86%, which may be potential new species or new genera.The results of Xinjiang Aydingkol Lake study showed that screed five kinds ofcarbon source used the BIOLOG method and they were raffinose, inositol, citric acid,mannose and mannitol respectively. There are71isolates from Aydingkol Lake soilsample were isolated by the filter carbon sources that added to the separation mediumand they belong to3phylum in bacteria domain via molecular biology identification.35isolates were belong Firmicutes bacteria and it is the most advantage bacteria(49.3%), and the most dominant strains belonging to Sediminibacillus genus; followedby Proteobacteria strains22strains (31%) and all belonging to the Halomonas genus;Actinobacteria14strains (19.7%) and the dominant genera are Nocardiopsis. These71strains classified in26OTU, among them15strains16s rRNA gene sequenceshomology with the nearest species are80.76%to96.86%, which may be potentialnew species or new genera.Halophilic bacteria of two Salt Lake in Xinjiang have highly rich biodiversityand both two lakes are Firmicutes bacteria predominate.This paper using an integratedapproach of BIOLOG Carbon source screening and culture-dependent methodsstudied that the two salt lakes may contain a wealth of new species of halophilicbacteria that have development of further research value.