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Plasmids, viruses and virus-like membrane vesicles from Thermococcales
Nicolas Soler1, Marie Gaudin, Evelyne Marguet
1Institut de Génétique et Microbiologie, Univ Paris-Sud 11, UMR 8621, CNRS 91405, Orsay, France.
Biochemical Society Transactions
|January 27, 2011
Summary
Plasmids and viruses (PVs) in hyperthermophilic archaea share genes and co-evolve with hosts. Membrane vesicles may facilitate PV transfer between archaeal species.
Area of Science:
- Microbiology
- Archaea Biology
- Molecular Biology
Background:
- Plasmids and viruses (PVs) are prevalent in hyperthermophilic archaea of the order Thermococcales.
- PVs exhibit diverse replication mechanisms, including rolling circle and theta mode.
- Novel DNA replication proteins are encoded by Thermococcales PVs, with homologs primarily found in other archaeal PVs.
Purpose of the Study:
- To investigate the genetic relatedness and co-evolutionary dynamics of plasmids and viruses in Thermococcales.
- To explore the role of virus-like membrane vesicles in the biology of hyperthermophilic archaea.
- To understand the potential mechanisms of genetic material transfer in these extreme environments.
Main Methods:
- Comparative genomics to analyze PV gene pools.
- Replication mechanism studies (inferred from sequence data).
- Analysis of virus-like membrane vesicle production and content.
Main Results:
- PVs from different families within Thermococcales share a common gene pool, indicating co-evolution with their hosts.
- Most Thermococcales produce virus-like membrane vesicles, analogous to eukaryotic ectosomes.
- The plasmid pTN1 was found within membrane vesicles of Thermococcus nautilus, suggesting a role in plasmid transfer.
Conclusions:
- Plasmids and viruses in Thermococcales are genetically interconnected and co-evolve with their hosts.
- Membrane vesicles produced by Thermococcales may serve as a vehicle for horizontal gene transfer, facilitating plasmid dissemination.
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