The goal of this study was to determine to what extent the Aquificales are related to the epsilon-Proteobacteria. The genome sequence of several members of this group as well as the genome sequence of Aquifex aeolicus are available. In this study we used information extracted from those whole-genome sequences to gain further insights into the relationships between these organisms, including the fraction of shared putative orthologous protein-encoding genes, dinucleotide relative abundance values and the sequences of the 16S rRNA gene and 20 housekeeping genes. The results of our analyses show that it is not straightforward to come to a consistent picture of the phylogenetic position of the order Aquificales but our data clearly show that there is no particularly close relationship between A. aeolicus and the epsilon-Proteobacteria as (i) they do not share more genes with each other than do other distantly related organisms and (ii) they do not share significant sequence similarity in many macromolecules. In addition, there is considerable evidence that confirms the placement of the Aquificales near the root of the bacterial tree.

中文翻译：

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从基因组学角度看水栖动物与ε-Proteobacteria之间的关系。

这项研究的目的是确定Aquificales在多大程度上与ε-Proteobacteria相关。该组的几个成员的基因组序列以及Aquifex aeolicus的基因组序列均可用。在这项研究中，我们使用从这些全基因组序列中提取的信息来深入了解这些生物之间的关系，包括共有的假定直系同源蛋白质编码基因的比例，二核苷酸相对丰度值以及16S rRNA基因和20的序列。看家基因。我们的分析结果表明，要获得一致的Aquificales的系统发育位置图并不容易，但是我们的数据清楚地表明A之间没有特别紧密的关系。aeolicus和epsilon-Proteobacteria的原因是：（i）与其他远距离相关的生物相比，它们彼此之间没有更多的基因共享；（ii）在许多大分子中，它们没有明显的序列相似性。另外，有相当多的证据证实了金龟子在细菌树根附近的位置。