Novel major archaebacterial group from marine plankton
Abstract
MARINE bacteria often dominate the plankton biomass1,2 and are responsible for much of the cycling of organic matter3, but bacterial diversity is poorly understood because conventional identification methods (requiring culturing) miss about 99% of the organisms4,5. Recent advances permit characterization of microbial communities by analysis of 16S ribosomal RNA gene sequences directly from biomass without the need to culture the organisms6; such studies from surface ocean samples have found only eubacteria7-10, not archaebacteria (or Archae11), which are profoundly different12. Here we report 16S rRNA sequences obtained from Pacific Ocean bacterioplankton samples collected from depths of 100 m and 500 m. Among these we found sequences only distantly related to those of any organisms previously characterized by 16S rRNA sequences, with similarities to the nearest such relatives (extreme thermophiles) approximately the same as those between animals and plants. We suggest that these sequences are from a previously undescribed archaebacterial group that may have diverged from the ancestors of characterized organisms very early in evolution.
- Publication:
-
Nature
- Pub Date:
- March 1992
- DOI:
- 10.1038/356148a0
- Bibcode:
- 1992Natur.356..148F