Ploidy and gene conversion in Archaea.

@article{Soppa2011PloidyAG,
  title={Ploidy and gene conversion in Archaea.},
  author={J{\"o}rg Soppa},
  journal={Biochemical Society transactions},
  year={2011},
  volume={39 1},
  pages={
          150-4
        }
}
  • J. Soppa
  • Published 1 February 2011
  • Biology
  • Biochemical Society transactions
The genome copy numbers of seven crenarchaeal species of four genera have been reported. All of them are monoploid and thus this seems to be a characteristic feature of Crenarchaeota. In stark contrast, none of six species representing six euryarchaeal genera is monoploid. Therefore Euryarchaea are typically oligoploid or polyploidy and their genome copy numbers are tightly regulated in response to growth phase and/or growth rate. A theoretical consideration called 'Muller's ratchet' predicts… 

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References

SHOWING 1-10 OF 19 REFERENCES

Genome Copy Numbers and Gene Conversion in Methanogenic Archaea

TLDR
It was shown that in the absence of selection very fast equalization of genomes in M. maripaludis took place probably via a gene conversion mechanism, and that the velocity of this phenomenon is inversely correlated to the strength of selection.

Regulated Polyploidy in Halophilic Archaea

TLDR
The results indicate that polyploidy might be more widespread in archaea (or even prokaryotes in general) than previously assumed, and the presence of so many genome copies in a proKaryote raises questions about the evolutionary significance of this strategy.

Frequent Recombination in a Saltern Population of Halorubrum

TLDR
Multi-locus sequence typing is used to demonstrate that haloarchaea exchange genetic information promiscuously, exhibiting a degree of linkage equilibrium approaching that of a sexual population.

Cell cycle characteristics of thermophilic archaea

TLDR
The in vivo organization of the chromosome DNA appeared to be different from that of eubacteria, as revealed by variation in the relative binding efficiency of different DNA stains.

Development of Additional Selectable Markers for the Halophilic Archaeon Haloferax volcanii Based on the leuB and trpA Genes

ABSTRACT Since most archaea are extremophilic and difficult to cultivate, our current knowledge of their biology is confined largely to comparative genomics and biochemistry. Haloferax volcanii

Cell Cycle Characteristics of Crenarchaeota: Unity among Diversity

TLDR
In Pyrobaculum, chromosome segregation overlapped with or closely followed DNA replication, and further genome separation appeared to occur concomitant with cellular growth, and cell division in P. aerophilum took place without visible constriction.

Nucleoid structure and partition in Methanococcus jannaschii: an archaeon with multiple copies of the chromosome.

TLDR
During entry into stationary phase, chromosome replication continued to termination while no new rounds were initiated: the cells ended up with one to five chromosomes per cell with no apparent preference for any given DNA content.

Isolation of acetate auxotrophs of the methane-producing archaeon Methanococcus maripaludis by random insertional mutagenesis.

TLDR
To learn more about autotrophic growth of methanococci, nine conditional mutants of Methanococcus maripaludis were isolated after transformation of the wild type with a random library in pMEB and insertion of pWDK104 into the genome was established.