Journal of Molecular Evolution

, Volume 25, Issue 2, pp 168–183

A view of early cellular evolution

  • Raik Mikelsaar
Article

DOI: 10.1007/BF02101759

Cite this article as:
Mikelsaar, R. J Mol Evol (1987) 25: 168. doi:10.1007/BF02101759

Summary

Some recent puzzling data on mitochondria put in question their place on the phylogenetic tree. A hypothesis, the archigenetic hypothesis, is presented, which generally agrees with Woese-Fox's concept of the common origin of eubacteria, archaebacteria, and eukaryotic hosts. However, for the first time, a case is made for the evolution of mitochondria from the ancient predecessors of pro- and eukaryotes (protobionts), not from eubacteria. Animal, fungal, and plant mitochondria are considered to be endosymbionts derived from independent free-living cells (mitobionts), which, having arisen at different developmental stages of protobionts, retained some of their ancient primitive features of the genetic code and the transcription-translation systems. The molecular-biological, bioenergetic, and paleontological aspects of this new concept of cellular evolution are discussed.

Key words

Cellular evolution Origin of mitochondria Phylogenetic tree Evolution of genetic code Ancient nucleic acids Rise of multicellularity Evolution of bioenergetics 

Copyright information

© Springer-Verlag New York Inc 1987

Authors and Affiliations

  • Raik Mikelsaar
    • 1
  1. 1.Institute of General and Molecular PathologyTartu State UniversityTartuEstonia, USSR