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PubMed · 3116275

A view of early cellular evolution.

R Mikelsaar
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Abstract

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.

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AnimalsBiological EvolutionDNA, MitochondrialGenetic CodeModels, GeneticPhylogenySpecies SpecificityComparative StudyJournal Article

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R Mikelsaar. 1987. A view of early cellular evolution.. https://doi.org/10.1007/bf02101759

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