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Does my genome look big in this?


This month's Genome Watch discusses selected recent genome papers that have examined the mechanisms and implications of reductive genome evolution.

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Figure 1: Remarkable repeat density in the Orientia tsutsugamushi genome.


  1. 1

    Lescot, M. et al. The genome of Borrelia recurrentis, the agent of deadly louse-borne relapsing fever, is a degraded subset of the tick-borne Borrelia duttonii. PLoS Genet. 4, e1000185 (2008).

    Article  PubMed  PubMed Central  Google Scholar 

  2. 2

    Darby, A. C. et al. Intracellular pathogens go extreme: genome evolution in the Rickettsiales. Trends Genet. 23, 511–520 (2007).

    CAS  Article  PubMed  Google Scholar 

  3. 3

    Cho, N. H. et al. The Orientia tsutsugamushi genome reveals massive proliferation of conjugative type IV secretion system and host-cell interaction genes. Proc. Natl Acad. Sci. USA 104, 7981–7986 (2007).

    CAS  Article  PubMed  Google Scholar 

  4. 4

    Nakayama, K. et al. The whole-genome sequencing of the obligate intracellular bacterium Orientia tsutsugamushi revealed massive gene amplification during reductive genome evolution. DNA Res. 15, 185–199 (2008).

    CAS  Article  PubMed  PubMed Central  Google Scholar 

  5. 5

    Hongoh, Y. et al. Complete genome of the uncultured Termite Group 1 bacteria in a single host protist cell. Proc. Natl Acad. Sci. USA 105, 5555–5560 (2008).

    CAS  Article  PubMed  PubMed Central  Google Scholar 

  6. 6

    Gil, R. et al. Massive presence of insertion sequences in the genome of SOPE, the primary endosymbiont of the rice weevil Sitophilus oryzae. Int. Microbiol. 11, 41–48 (2008).

    CAS  PubMed  Google Scholar 

  7. 7

    Anderson, I. et al. Genome sequence of Thermofilum pendens reveals an exceptional loss of biosynthetic pathways without genome reduction. J. Bacteriol. 190, 2957–2965 (2008).

    CAS  Article  PubMed  PubMed Central  Google Scholar 

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Entrez Genome Project

Borrelia duttonii

Borrelia recurrentis

Orientia tsutsugamushi

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Walker, A., Langridge, G. Does my genome look big in this?. Nat Rev Microbiol 6, 878–879 (2008).

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