Analysis on cell filament and phenotypic plasticity of Eschericia coli using microfluid system

• Project/Area Number: 24657014
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Ecology/Environment
• Research Institution: The University of Tokyo
• Principal Investigator: SHIMADA Masakazu 東京大学, 大学院情報学環, 教授 (40178950)
• Co-Investigator(Renkei-kenkyūsha): WKAMOTO Yuichi 東京大学, 大学院総合文化研究科, 准教授 (30517884) ; YOSHIDA Tkehito 東京大学, 大学院総合文化研究科, 准教授 (40447321) ; OHBAYASHI Kako 東京大学, 大学院総合文化研究科, 特任研究員 (20448202)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Project Status: Completed (Fiscal Year 2014)
• Budget Amount: ¥3,900,000 (Direct Cost: ¥3,000,000、Indirect Cost: ¥900,000); Fiscal Year 2014: ¥780,000 (Direct Cost: ¥600,000、Indirect Cost: ¥180,000); Fiscal Year 2013: ¥780,000 (Direct Cost: ¥600,000、Indirect Cost: ¥180,000); Fiscal Year 2012: ¥2,340,000 (Direct Cost: ¥1,800,000、Indirect Cost: ¥540,000)
• Keywords: 一細胞培養系 / 大腸菌 / 細胞伸長 / 表現型可塑性 / 細胞密度 / recA遺伝子発現 / 環境ストレス / 1細胞培養計測系 / SOS応答 / recA遺伝子の発現 / 密度依存性 / プロモーター活性 / 細胞分裂 / 変動環境 / ストレス / 貧栄養環境 / SOS遺伝子の発現 / マイクロ流路 / 貧栄養 / SOS反応 / 遺伝的順応

Outline of Final Research Achievements

Using the single cell incubation, we analyzed three potential factors affecting the cell filament formation of Escherichia coli ; (A) the enemy avoidance hypothesis, (B) the cell performance enhanced at a low density, and (C) the environmental stress. We analyzed relationship of cell filament to cell density and recA gene expression in the batch incubation. Results showed that recA gene was highly expressed in some cells (“high recA cell”) and that they were elongated. The higher the cell density became, the higher frequencies of filament cells and high recA cells showed. Increase of cell density results in increasing wastes and insufficient trophic matters, then environmental stress increases, following the cell filament formation and the recA gene expression.

Research Products

• [Journal Article] Sex allocation pattern of the diatom Cyclotella meneghiniana. (2013)
  • Author(s): Shirokawa, Y. and Shimada, M.
  • Journal Title: Proc. R. Soc. Biol. Sci. Volume: 280 Issue: 1761 Pages: 20130503-20130503
  • DOI: 10.1098/rspb.2013.0503
  • Peer Reviewed
• [Journal Article] Sex allocation pattern of the diatom Cyclotella meneghiniana. (2013)
  • Author(s): Shirokawa Y. and Shimada M.
  • Journal Title: Proceedings - Royal Society. Biological sciences Volume: 280
  • Peer Reviewed
• [Journal Article] DynamicPersistence of Antibiotic-StressedMycobacteria (2013)
  • Author(s): Wakamoto, Y., Dhar, N., Chait, R.,Schneider, K., Signorino-Gelo, F.,Leibler, S., McKinney, J. D.
  • Journal Title: Science Volume: 339(6115) Issue: 6115 Pages: 91-95
  • DOI: 10.1126/science.1229858
  • Peer Reviewed
• [Presentation] Inconsistency between population and single cell growth rates revealed by dynamics cytometer.
  • Author(s): Wakamoto, Y.
  • Organizer: 第50回日本生物物理学会
  • Place of Presentation: 名古屋大学（愛知県、名古屋市）
• [Presentation] Phenomenological rules behind clonal proliferation of bacteria.
  • Author(s): Wakamoto, Y.
  • Organizer: 第35回日本分子生物学会年会
  • Place of Presentation: 福岡国際会議場（福岡市）
• [Remarks] Shimada-Lab
  • URL: http://park.itc.u-tokyo.ac.jp/shimada-lab/
• [Remarks] Shimada-Lab
  • URL: http://park.itc.u-tokyo.ac.jp/shimada-lab/
• [Remarks] Shimada-Lab
  • URL: http://park.itc.u-tokyo.ac.jp/shimada-lab/