Early evolution of eukaryotic microorganisms in Archean oxygen oasis produced by cyanobacteria

• Project/Area Number: 24654162
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Geology
• Research Institution: Nagoya University
• Principal Investigator: SUGITANI Kenichiro 名古屋大学, 環境学研究科, 教授 (20222052)
• Co-Investigator(Kenkyū-buntansha): MIMURA Koichi 名古屋大学, 大学院環境学研究科, 准教授 (80262848) ; ASAHARA Yoshihiro 名古屋大学, 大学院環境学研究科, 助教 (10281065) ; TAKEUCHI Makoto 名古屋大学, 大学院環境学研究科, 教授 (80273217)
• 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: ¥650,000 (Direct Cost: ¥500,000、Indirect Cost: ¥150,000); Fiscal Year 2013: ¥1,040,000 (Direct Cost: ¥800,000、Indirect Cost: ¥240,000); Fiscal Year 2012: ¥2,210,000 (Direct Cost: ¥1,700,000、Indirect Cost: ¥510,000)
• Keywords: 真核生物 / 太古代 / 酸素オアシス / シアノバクテリア / ピルバラクラトン / 微化石 / 局所同位体分析 / 生物多様性 / アクリターク / 珪質ストロマトライト / 珪質シンター / 国際情報交換 / 炭素同位体分析

Outline of Final Research Achievements

We performed detailed studies on Archean microfossils collected from multiple localities in the 3.0 Ga Farrel Quartzite (FQ) in the Pilbara Craton, Western Australia, with referring to the 3.4 Ga Strelley Pool microfossils (stored in Nagoya University). The PI has discovered some very important specimens including large lenses with single to several objects inside, which provide constraint on biological affinity (eukaryotic) of lenticular microfossils. Also high resolution SEM analyses revealed that sheet-like appendage (flange) is composed of fine meshwork, which suggests the possibility that the structure is constructed and maintained by cytoskeleton. Also carbon isotopic values of individual microfossils were determined, revealing that their data are distinct from the isotopic values of the matrix carbonaceous particles. Concentration of phosphorous and nitrogen in the structures was also confirmed. With these results, the biogenicity of FQ microfossils is firmly established.

Research Products

• [Journal Article] Carbon isotopic analyses of ~3.0 Ga microstructures imply planktonic autotrophs inhabited the Earth’s early oceans (2013)
  • Author(s): House, C.H., Oehler, D.Z., Sugitani, K., Mimura, K.
  • Journal Title: Geology Volume: 41 Issue: 6 Pages: 651-654
  • DOI: 10.1130/g34055.1
  • Peer Reviewed
• [Journal Article] Texture-specific isotopic compositions in 3.4 Gyr old organic matter support selective preservation in cell-like structures (2013)
  • Author(s): Lepot, K., Williford, K.H., Ushikubo, T., Sugitani, K., Mimura, K., Spicuzza, M.J., Valley, J.W.
  • Journal Title: Geochimica et Cosmochimica Acta Volume: 112 Pages: 66-86
  • Peer Reviewed
• [Journal Article] Carbon isotopic analyses of ~3.0 Ga microstructures imply planktonic autotrophs inhabited the Earth’s early oceans (2013)
  • Author(s): C.H. House1, D.Z. Oehler2, K. Sugitani, and K. Mimura
  • Journal Title: Geology Volume: ？
  • Peer Reviewed
• [Presentation] Biogenicity of Archean carbonaceous microstructures: a NanoSIMS study of the putative microfossils of the Farrel Quartzite (3 Gyr) (2015)
  • Author(s): Delarue F, Robert F, Sugitani K, Duhamel R, Pont S, Gonzalez-Cano A, Mostefaoui S, Derenne S
  • Organizer: Goldschmidt2015
  • Place of Presentation: プラハ、チェコ共和国
  • Year and Date: 2015-08-16 – 2015-08-21
• [Presentation] Isotopic and nanoscale textural evidence for the biogenicity of 3.4 billion years old cell-like structures (2013)
  • Author(s): Lepot, K., Williford, K.H., Ushikubo, T., Sugitani, K., Mimura, K., Spicuzza, M.J., Valley, J.W.
  • Organizer: The International Biogeoscience Conference 2013 Nagoya, Japan
  • Place of Presentation: 名古屋大学
• [Presentation] In situ, spatially resolved biosignature detection at the microbial scale (2013)
  • Author(s): Wiiliford, K.H., Eigenbrode, J.L., Hallmann, C., Kitajima, K., KOzdon, R., Kudryavtesev, A., Lepot, K., Schopf, J.W., Spicuzza, M.J., Sugitani, K., Summons, R.E., Ushikubo, T., Van Kranendonk, M.J., Valley, J.W.
  • Organizer: The International Biogeoscience Conference 2013 Nagoya, Japan
  • Place of Presentation: 名古屋大学
• [Presentation] Ultrastructural evidence for biogenicity of Archean organ-walled microfossils (2013)
  • Author(s): Javaux, E.J., Lepot, K., Sugitani, K.
  • Organizer: The International Biogeoscience Conference 2013 Nagoya, Japan
  • Place of Presentation: 名古屋大学
• [Presentation] Palynology of lenticular microfossils from the 3.4 Ga Strelley Pool Formation, Western Australia: Do they represent early eukaryotic lineage? (2013)
  • Author(s): Sugitani,K., Mimura, K., Takeuchi, M., Lepot, K., Javaux, E.J.
  • Organizer: The International Biogeoscience Conference 2013 Nagoya, Japan
  • Place of Presentation: 名古屋大学