Diversity Of Actinobacteria And The Cloning And Analysis Of Ectoine Biosynthesis Genes Cluster Of 2 Moderately Halophilic Actinomycetes From Lop Nur

Lop Nur located in east of Tarim Basin,which is a high-temperature,drought and high salt concentration.Due to its specific geographical environment and topography features,the specific ecological environment offers rich microbial resources and most of them are still unknown.They often have specific physiology to adapt to the specific circumstances.Thus,they are good materials for the study of diversity of actinobacteria and the adaptation mechanism in moderate halophile.The soil sample was collected from a hypersaline habitat in Lop Nur,Xinjiang Province.Totally 16 genus contained 60 species were isolated using 8 kinds of medium with different salt concentration gradient.,which is Streptomyces,Nocardiopsis,Prauserella,Amycolatopsis,Nesterenkonia,Myceligenerans,Actinopolymorpha,Haloglycomyces,Haloactinospora,Actinopolyspora,Glycomyces,Haloglycomyces,Haloactinopolyspora,Saccharomonospora,Streptomonospora,Kocuria and Isoptericola and 3 genus are the dominant communities,which is Streptomyces,Nocardiopsis and Prauserella.11 isolates are probably belonged to new taxons and 16S rDNA sequences of these isolates showed similarity less than 97%to the identified isolates in database of NCBI.In accordance with the principle of polyphasic taxonomy,a systematic study had been conducted on the taxonomy of three novel isolates.Phylogenetic analysis showed that strain TRM 49117 represents a novel species within the genus Glycomyces for which the name Glycomyces fuscus sp.nov.is proposed,the type strain is TRM 49117T;Strain TRM 49136 represents a novel species within the genus Glycomyces for which the name Glycomyces albus sp.nov.is proposed,the type strain is TRM 49136T;Strain TRM 49201 represents a novel species within the genus Haloglycomyces for which the name Haloglycomyces xinjiangensis sp.nov.is proposed,the type strain is TRM 49201T.Analyzed the ectoine biosynthetic gene(ectABC gene)of the strains TRM 45540 and TRM 40136,the result shows that the ectoine biosynthetic gene of TRM 45540 has totally 2403 nuvleotides,and TRM 40136 has totally 2411 nuvleotides.By BLAST sequences analysis,we find that TRM 45540 ectABC gene has a high nomology with many nucleotide sequences in GenBank database,protein sequences comparison and the constructive result of phylogeny show that the TRM 45540 has closest evolutionary relationship with Streptomyces sp.TOR3209;TRM 40136 was potential novel genes.