新疆于田盐池放线菌群落结构

Actinobacterial Community Structure of a Soil Sample from Yutian Pit in Xinjiang Revealed by Culture-independent Method

摘要:

应用免培养技术和基于16S rRNA基因序列的系统发育分析对新疆于田盐池土壤放线菌群落结构进行研究。结果表明, 41个克隆序列属于26个OTUs, 分别分布于放线菌门放线菌亚纲(Actinobacteridae)的7个亚目和酸微菌亚纲(Acidimicrobidae), 其中链孢囊菌亚目(Streptosporangi- neae)中放线菌组成丰富, 占到了全部挑选克隆的42.3%, 是于田盐池放线菌群落中的优势菌, 而链霉菌不是高盐环境放线菌的优势菌群。在这些克隆序列中有71.8% 的克隆序列同已知序列的相似性低于97%, 属于放线菌的新类群, 这些可能的新类群中有15.3%的克隆序列与已知菌株的相似性小于85%, 这些克隆序列的分类地位都在科一级的分类单元上, 有的可能分类地位更高。这些研究结果说明于田盐池中存在有较为丰富的放线菌系统发育多样性, 并且潜藏着新类型的放线菌资源。另外, 由于微生态效应的存在, 不同高盐环境之间放线菌群落也存在明显差异。

关键词:于田盐池, 系统发育, 放线菌群落, 免培养方法

Abstract:

Actinobacterial community structure in a soil sample from Yutian pit in Xinjiang was investigated by using Culture-independent method and phylogenetic analysis based on 16S rRNA gene sequences. The result showed 41 clones distribute in 26 OTUs, which exist in Acidimicrobidae and 7 suborders of Actinobacteridae respectively, especially the dominant community of Yutian pit was streptosporangineae instead of streptomycete, which accounting for 42.3% of sequenced clones. The similarity between 71.8% of 41 detected sequences and published clone sequences were less than 97%, which represented a new community and 15.3% of the clone sequences which identitied with GenBank clone sequences were under 85%, which may represent some new families or suborders. The results indicated that abundant actinobacterial community and new actinobacterial resources existed in Yutian pit. In addition, actinomycete community which exist in different high salt concentration environment have distinct differences for microecological effection.

Key words:Yutian pit, Phylogenetic analysis, Actinobacterial community structure, Culture-independent method