Department of Molecular Evolution, Centro de Astrobiología (CSIC-INTA), Torrejón de Ardoz, Madrid, Spain.
FEMS Microbiol Ecol. 2011 Jul;77(1):165-75. doi: 10.1111/j.1574-6941.2011.01095.x. Epub 2011 Apr 15.
The diversity of archaeal communities growing in four hot springs (65-90 °C, pH 6.5) was assessed with 16S rRNA gene primers specific for the domain Archaea. Overall, mainly uncultured members of the Desulfurococcales, the Thermoproteales and the Korarchaeota, were identified. Based on this diversity, a set of chaperonin heat-shock protein (Hsp60) gene sequences from different archaeal species were aligned to design two degenerate primer sets for the amplification of the chaperonin gene: Ths and Kor (which can also detect the korarchaeotal chaperonin gene from one of the samples). A phylogenetic tree was constructed using the chaperonin sequences retrieved and other sequences from cultured representatives. The Alpha and Beta paralogs of the chaperonin gene were observed within the main clades and orthologs among them. Cultivated representatives from these clades were assigned to either paralog in the chaperonin tree. Uncultured representatives observed in the 16S rRNA gene analysis were found to be related to the Desulfurococcales. The topologies of the 16S rRNA gene and chaperonin phylogenetic trees were compared, and similar phylogenetic relationships were observed. Our results suggest that the chaperonin Hsp60 gene may be used as a phylogenetic marker for the clades found in this extreme environment.
采用针对古菌域的 16S rRNA 基因引物，评估了在四个温泉（65-90°C，pH6.5）中生长的古菌群落的多样性。总体上，主要鉴定出未培养的脱硫球菌目、热变形菌目和泉古菌门成员。基于这种多样性，从不同古菌物种设计了一组伴侣蛋白热休克蛋白（Hsp60）基因序列，以设计用于扩增伴侣蛋白基因的两套简并引物：Ths 和 Kor（也可以检测到其中一个样本中的泉古菌伴侣蛋白基因）。使用检索到的伴侣蛋白序列和其他培养代表序列构建了一个系统发育树。在主要支系中观察到伴侣蛋白基因的 Alpha 和 Beta 等位基因，并在它们之间观察到直系同源物。在伴侣蛋白树中，将这些支系中的培养代表分配到伴侣蛋白基因的一个等位基因中。在 16S rRNA 基因分析中观察到的未培养代表与脱硫球菌目有关。比较了 16S rRNA 基因和伴侣蛋白系统发育树的拓扑结构，观察到了相似的系统发育关系。我们的结果表明，伴侣蛋白 Hsp60 基因可用作该极端环境中发现的进化枝的系统发育标记。
