Barns S M, Delwiche C F, Palmer J D, Pace N R
Department of Biology, Indiana University, Bloomington 47405, USA.
Proc Natl Acad Sci U S A. 1996 Aug 20;93(17):9188-93. doi: 10.1073/pnas.93.17.9188.
Phylogenetic analysis of ribosomal RNA sequences obtained from uncultivated organisms of a hot spring in Yellowstone National Park reveals several novel groups of Archaea, many of which diverged from the crenarchaeal line of descent prior to previously characterized members of that kingdom. Universal phylogenetic trees constructed with the addition of these sequences indicate monophyly of Archaea, with modest bootstrap support. The data also show a specific relationship between low-temperature marine Archaea and some hot spring Archaea. Two of the environmental sequences are enigmatic: depending upon the data set and analytical method used, these sequences branch deeply within the Crenarchaeota, below the bifurcation between Crenarchaeota and Euryarchaeota, or even as the sister group to Eukaryotes. If additional data confirm either of the latter two placements, then the organisms represented by these ribosomal RNA sequences would merit recognition as a new kingdom, provisionally named "Korarchaeota."
对从黄石国家公园一处温泉中未经培养的生物体获取的核糖体RNA序列进行系统发育分析，发现了几个新的古菌群体，其中许多群体在该界先前已鉴定的成员之前就从泉古菌的世系中分化出来。添加这些序列构建的通用系统发育树表明古菌是单系的，自展支持率适中。数据还显示了低温海洋古菌与一些温泉古菌之间的特定关系。其中两个环境序列很神秘：根据所使用的数据集和分析方法，这些序列在泉古菌门内分支很深，位于泉古菌门和广古菌门的分叉点之下，甚至作为真核生物的姐妹群。如果更多数据证实了后两种定位中的任何一种，那么这些核糖体RNA序列所代表的生物体将值得被认可为一个新的界，暂命名为“泉古菌界”。
