Huber Harald, Hohn Michael J, Rachel Reinhard, Fuchs Tanja, Wimmer Verena C, Stetter Karl O
Lehrstuhl für Mikrobiologie und Archaeenzentrum, Universität Regensburg, Universitätsstrasse 31, D-93053 Regensburg, Germany.
Nature. 2002 May 2;417(6884):63-7. doi: 10.1038/417063a.
According to small subunit ribosomal RNA (ss rRNA) sequence comparisons all known Archaea belong to the phyla Crenarchaeota, Euryarchaeota, and--indicated only by environmental DNA sequences--to the 'Korarchaeota'. Here we report the cultivation of a new nanosized hyperthermophilic archaeon from a submarine hot vent. This archaeon cannot be attached to one of these groups and therefore must represent an unknown phylum which we name 'Nanoarchaeota' and species, which we name 'Nanoarchaeum equitans'. Cells of 'N. equitans' are spherical, and only about 400 nm in diameter. They grow attached to the surface of a specific archaeal host, a new member of the genus Ignicoccus. The distribution of the 'Nanoarchaeota' is so far unknown. Owing to their unusual ss rRNA sequence, members remained undetectable by commonly used ecological studies based on the polymerase chain reaction. 'N. equitans' harbours the smallest archaeal genome; it is only 0.5 megabases in size. This organism will provide insight into the evolution of thermophily, of tiny genomes and of interspecies communication.
根据小亚基核糖体RNA（ss rRNA）序列比较，所有已知古菌都属于泉古菌门、广古菌门，以及——仅由环境DNA序列表明——“科古菌门”。在此，我们报告了从一个海底热泉中培养出一种新的超嗜热纳米古菌。这种古菌不能归属于上述任何一个类群，因此必定代表一个未知的门，我们将其命名为“纳古菌门”，以及一个物种，我们将其命名为“嗜热栖热纳古菌”。“嗜热栖热纳古菌”的细胞呈球形，直径仅约400纳米。它们生长在一种特定古菌宿主——火球菌属的一个新成员——的表面。到目前为止，“纳古菌门”的分布情况尚不清楚。由于它们不同寻常的ss rRNA序列，基于聚合酶链反应的常用生态学研究一直未能检测到其成员。“嗜热栖热纳古菌”拥有最小的古菌基因组；其大小仅为0.5兆碱基。这种生物体将为嗜热习性、微小基因组以及种间交流的进化提供见解。
