Study On Isolation And Ecological Distribution Of Rare Actinomycetes From Tarim Basin

In order to understand the diversity and distribution features of rare actionmyce tes in Tarim basin, actinomycete resources were utilized effectively. In this research, rare actinomycetes were collected and isolated from 25 samples of Tarim basin. Ecol-ogical environment, soil properties, vegetation and the correlation between distribute-on of rare actinomycetes were analyzed. The strains with the gene of PKS-â… and PKS-â…¡were selected.(1) comparing separation methods, the combination inhibitors(potassium dichromate,cycloheximide and nystatin) were established. By the pre-treatment methods of dry-hot, SDS and phenol, the samples were selected by 7 culture medium. The results showed the amount of isolation from high to low was dry-hot, SDS and phenol.(2) The strains were identified by 16S rDNA molecular identification, the colony morphology and microscopic observation.25 kinds of strains were rare actinomycetes. which belonged to 12 genera. They were Rhodococcus, Micromonospora, Saccharopolys-pora, Nonomuraea, Saccharothrix, Saccharomonspora, Brevibacteriaceae, Pseudonocardia, Glycomyces, Nocardia, Actinomadura, Planomonospora. They covered 6 suborders and 7 families in actinomycetes classification system.(3) From ecological eara, the results showed that species of distribution of rare actinomycetes belonged to 9 genera:I-5-a:loamy and desert ecoregion in Northern of Tarim Basin(Micromonospora,Saccharopolyspora, Nonomuraea, Saccharothrix, Saccharomonspora, Pseudonocardia, Glycomyces, Nocardia, Actinomadura),I-5-j: the riparian forest ecoregion in Tarim Basin(Micromonospora,Saccharopolyspora, Nonomuraea, Saccharothrix, Saccharomonspora, Brevibacteriaceae, Glycomyces, Nocardia, Actinomadura).I-5-b:west of hetian river ecoregion in taklimakan desert(Actinomadura Planomonospora Pseudonocardia Brevibacteriaceae, Micro-monospora, Saccharopolyspora, Nonomuraea, Saccharothrix, Saccharomonspora,). the least is the loamy and desert ecoregion in Southern of Tarim Basin(Rhodococcus Nocardia). from soil properties angle to analysis that the cultivated soil and the soil which have more organic matter and more loose have more rare actinomycetes.(4) Amplification of PKS-â… and PKS-â…¡showed that two strains 36 and 16110 have the PKS-â… gene and belong to Saccharothrix and Saccharopolyspora, the two strains P21 and 321 have the PKS-â…¡gene and belong to Pseudonocardia and Nonomuraea.the each detection rate is 8%.