Franklin M. Harold
- Published in print:
- 2014
- Published Online:
- May 2015
- ISBN:
- 9780226174143
- eISBN:
- 9780226174310
- Item type:
- chapter
- Publisher:
- University of Chicago Press
- DOI:
- 10.7208/chicago/9780226174310.003.0007
- Subject:
- Biology, Biochemistry / Molecular Biology
The origin of eukaryotic cells is a mystery second only to the origin of life itself. The problem is that eukaryotes make up a distinctive clade, conspicuously different from prokaryotes, yet they ...
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The origin of eukaryotic cells is a mystery second only to the origin of life itself. The problem is that eukaryotes make up a distinctive clade, conspicuously different from prokaryotes, yet they share genes and traits with both Bacteria and Archaea. There is general agreement that eukaryotes are chimaeric, since mitochondria and plastids derive from Bacterial endosymbionts; but consensus ends here. Disputes swirl around the nature of the cells that hosted those symbionts, the nature and timing of their association, and the role of the symbionts in generating eukaryotic complexity. This long-running controversy may now be approaching a resolution that combines ideas from several camps. The emerging synthesis postulates an “urkaryote” of Archaeal affinities that diverged very early and came to make its living by scavenging and predation upon the primary producers of organic matter. Acquisition of the Bacterial precursors of mitochondria enhanced the consortium's energy economy, and underwrote the rise of complex eukaryotic cells.Less
The origin of eukaryotic cells is a mystery second only to the origin of life itself. The problem is that eukaryotes make up a distinctive clade, conspicuously different from prokaryotes, yet they share genes and traits with both Bacteria and Archaea. There is general agreement that eukaryotes are chimaeric, since mitochondria and plastids derive from Bacterial endosymbionts; but consensus ends here. Disputes swirl around the nature of the cells that hosted those symbionts, the nature and timing of their association, and the role of the symbionts in generating eukaryotic complexity. This long-running controversy may now be approaching a resolution that combines ideas from several camps. The emerging synthesis postulates an “urkaryote” of Archaeal affinities that diverged very early and came to make its living by scavenging and predation upon the primary producers of organic matter. Acquisition of the Bacterial precursors of mitochondria enhanced the consortium's energy economy, and underwrote the rise of complex eukaryotic cells.