Send to

Choose Destination
Syst Appl Microbiol. 1991;14(4):305-10.

A definition of the domains Archaea, Bacteria and Eucarya in terms of small subunit ribosomal RNA characteristics.

Author information

Mathematics and Computer Science Division, Argonne National Laboratory, IL 60439, USA.
U IL, Urbana, Dept Microbiology


The number of small subunit rRNA sequences is now great enough that the three domains Archaea, Bacteria and Eucarya (Woese et al., 1990) can be reliably defined in terms of their sequence "signatures". Approximately 50 homologous positions (or nucleotide pairs) in the small subunit rRNA characterize and distinguish among the three. In addition, the three can be recognized by a variety of nonhomologous rRNA characters, either individual positions and/or higher-order structural features. The Crenarchaeota and the Euryarchaeota, the two archaeal kingdoms, can also be defined and distinguished by their characteristic compositions at approximately fifteen positions in the small subunit rRNA molecule.

[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center