Thermoproteales-a third order of thermoacidophilic archaebacteria
Abstract
The prokaryotic domain has been divided into the urkingdoms of the eubacteria and the archaebacteria on the basis of comparison of their 16S rRNA sequences1-3. Differences in their cell walls4, membrane lipids5 and mechanisms of transcription6 and translation7-10 provide further evidence for this division. The demarcation of two branches of archaebacteria, the methanogens, including the extreme halophiles11-13, in one branch, and the thermoacidophiles, represented by the two orders Sulfolobus14 and Thermoplasma15, on the other, is based on physiology and on a comparison of component patterns of DNA-dependent RNA polymerases16-20 rather than rRNA sequences. We show here that Thermoproteus tenax, a novel anaerobic, sulphur-respiring, multiform thermoacidophilic archaebacterium isolated from solfataric springs of Iceland21, represents a third order of the thermoacidophilic branch of archaebacteria and suggests a specific relationship between thermoacidophilic archaebacteria and primitive eukaryotes such as yeast.
- Publication:
-
Nature
- Pub Date:
- September 1981
- DOI:
- 10.1038/293085a0
- Bibcode:
- 1981Natur.293...85Z