腾冲两热泉泉古菌多样性及系统发育的初步分析

Crenarchaeal Diversity and Phylogenetic Analysis of Two Hot Springs in Tengchong

摘要:

通过构建16S rRNA 基因片段的克隆文库对腾冲热海两温泉中泉古菌的多样性和系统发育关系进行了初步的研究。一共得到 18 个泉古菌克隆序列, 可分为 12 个OTUs, 两温泉的克隆序列与已知GenBank上关系最近序列的平均相似性较低, 无名泉为 92.56%, 热爆区为 93%。从基于16S rRNA基因片段序列构建的系统发育树来看, 74℃ 的无名泉样点中既有属于超高温环境类群的泉古菌, 同时又有属于和常温环境较接近的泉古菌; 45℃ 的热爆区样点的泉古菌, 相对来说则更接近于常温类群。本次研究表明, 腾冲热泉与世界其它同类热泉之间的泉古菌类群存在着一定的差异; 而且两实验样点代表了超高温和高温环境泉古菌逐渐向常温过度的两个重要环境。

Abstract:

The crenarchaeal diversity and phylogenesis of two hot springs in Tengchong were investigated and analyzed using the construction of 16S rRNA gene clone libraries. Total 18 crenarchaeal sequences were obtained and divided into 12 OTUs. The average similarities between the clone sequences from Wuming hot spring and Rebao hot spring and their closest sequences deposited in GenBank is 92.56% and 93%, respectively. Based on the phylogenetic tree constructed by using crenarchaeal 16S rRNA gene sequences, Wuming hot spring not only have hyperthethermophilic crenarchaeal clusters but also have the crenarchaeal clusters that have close phylogenetic relationship with non-thermophilic crenarchaeota. And most of the crenarchaeota in Rebao spring distribute in normal temperature groups. This study showed that crenarchaeal clusters in Tengchong hot springs have some differences with other hot springs in the world, and these springs represent two important environments for investigating the evolutionary origin of the non-thermophilic Crenarchaeoone library.