Analysis of maintenance mechanism of genome structure by bacterial methylome and IS transposition assay.

• Project/Area Number: 16K14892
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Applied microbiology
• Research Institution: Tokyo University of Agriculture
• Principal Investigator: YOSHIKAWA Hirofumi 東京農業大学, 生命科学部, 教授 (50175676)
• Project Period (FY): 2016-04-01 – 2018-03-31
• Project Status: Completed (Fiscal Year 2017)
• Budget Amount: ¥3,640,000 (Direct Cost: ¥2,800,000、Indirect Cost: ¥840,000); Fiscal Year 2017: ¥1,820,000 (Direct Cost: ¥1,400,000、Indirect Cost: ¥420,000); Fiscal Year 2016: ¥1,820,000 (Direct Cost: ¥1,400,000、Indirect Cost: ¥420,000)
• Keywords: メチローム / シトシンメチル化 / 挿入配列 / トランスポゼース / アデニンメチル化 / 親鎖識別機構 / 胞子形成 / 誤対合修復 / 実験進化 / 分子シャペロン / 遺伝子発現 / 進化

Outline of Final Research Achievements

In terms of maintenance mechanisms of genome structure, we focused on two phenomena, methylation and IS transposition. Bacterial epigenetics has been noted only recently and correlation with growth regulation is totally unknown. In this study, we demonstrated sporulation specific methylation in Bacillus subtilis. While transposition of IS derived from natto strain has been found to be strictly dependent on recA gene, its essential function on IS transposition was not homologous recombination but ATP hydrolysis activity. In addition, we explored the possible evolutionary background of the unique feature of 168 genome which harbored no IS element. Successive culture of 168 cells with our newly developed IS transposition assay system revealed that 168 cells allowed IS transposition to some extent, but later inhibitory effect of IS transposition seemed to emerge by inactivating transposase activity. Those transposition-capable cells grew slowly and would be titrate out during evolution.

Research Products

• [Journal Article] Transposition of insertion sequence IS<i>256Bsu1</i> in <i>Bacillus subtilis</i> 168 is strictly dependent on <i>recA</i> (2017)
  • Author(s): Akashi M, Harada S, Moki S, Okouji Y, Takahashi K, Kada S, Yamagami K, Sekine Y, Watanabe S, Chibazakura T, Yoshikawa H.
  • Journal Title: Genes & Genetic Systems Volume: 92 Issue: 2 Pages: 59-71
  • DOI: 10.1266/ggs.16-00071
  • NAID: 130006172746
  • ISSN: 1341-7568, 1880-5779
  • Peer Reviewed / Open Access / Acknowledgement Compliant
• [Presentation] 人為的IS誘導が枯草菌168株に与える影響の解析 (2018)
  • Author(s): 徳山麻里、原田翔太，兼崎友、朝井計、吉川博文
  • Organizer: 日本ゲノム微生物学会
• [Presentation] 枯草菌168 株が挿入配列を持たない理由の解明 (2018)
  • Author(s): 徳山麻里，吉川博文，朝井計，原田翔太，兼崎友
  • Organizer: 日本農芸化学会
• [Presentation] 枯草菌分子シャペロンによる変異緩衝作用の検証 (2017)
  • Author(s): 北村 夏美、法花津 匠、大塚 まみ、武井 若紗、小菅 是子、吉川 博文
  • Organizer: 日本農芸化学会
  • Place of Presentation: 京都女子大学（京都市）
  • Year and Date: 2017-03-19
• [Presentation] 枯草菌分子シャペロンGroES/Lによる変異の蓄電池機能 (2017)
  • Author(s): 北村夏美、法花津匠、大塚まみ、武井若紗、小菅是子、吉川博文
  • Organizer: 日本ゲノム微生物学会
  • Place of Presentation: 慶應義塾大学湘南藤沢キャンパス（藤沢市）
  • Year and Date: 2017-03-02