The whole-genome sequencing of the obligate intracellular bacterium orientia tsutsugamushi revealed massive gene amplification during reductive genome evolution

Keisuke Nakayama, Atsushi Yamashita, Ken Kurokawa, Takuya Morimoto, Michihiro Ogawa, Masahiro Fukuhara, Hiroshi Urakami, Makoto Ohnishi, Ikuo Uchiyama, Yoshitoshi Ogura, Tadasuke Ooka, Kenshiro Oshima, Akira Tamura, Masahira Hattori, Tetsuya Hayashi*

*この研究の対応する著者

研究成果: Article査読

117 被引用数 (Scopus)

抄録

Scrub typhus ('Tsutsugamushi' disease in Japanese) is a mite-borne infectious disease. The causative agent is Orientia tsutsugamushi, an obligate intracellular bacterium belonging to the family Richettsiaceae of the subdivision alpha-Proteobacteria. In this study, we determined the complete genome sequence of O. tsutsugamushi strain lkeda, which comprises a single chromosome of 2 008 987 bp and contains 1967 protein coding sequences (CDSs). The chromosome is much larger than those of other members of Rickettsiaceae, and 46.7% of the sequence was occupied by repetitive sequences derived from an integrative and conjugative element, 10 types of transposable elements, and seven types of short repeats of unknown origins. The massive amplification and degradation of these elements have generated a huge number of repeated genes (1196 CDSs, categorized into 85 families), many of which are pseudogenes (766 CDSs), and also induced intensive genome shuffling. By comparing the gene content with those of other family members of Rickettsiacea, we identified the core gene set of the family Rickettsiaceae and found that, while much more extensive gene loss has taken place among the housekeeping genes of Orientia than those of Rickettsia, O. tsutsugamushi has acquired a large number of foreign genes. The O. tsutsugamushi genome sequence is thus a prominent example of the high plasticity of bacterial genomes, and provides the genetic basis for a better understanding of the biology of O. tsutsugamushi and the pathogenesis of 'Tsutsugamushi' disease.

本文言語English
ページ(範囲)185-199
ページ数15
ジャーナルDNA Research
15
4
DOI
出版ステータスPublished - 2008
外部発表はい

ASJC Scopus subject areas

  • 遺伝学
  • 分子生物学
  • 医学(全般)

フィンガープリント

「The whole-genome sequencing of the obligate intracellular bacterium orientia tsutsugamushi revealed massive gene amplification during reductive genome evolution」の研究トピックを掘り下げます。これらがまとまってユニークなフィンガープリントを構成します。

引用スタイル