Study of Dynamical Aspect of Photosynthetic Proteins Observed with the Newly Developed Cryogenic Microscope

2014 Fiscal Year Final Research Report

• Project/Area Number: 24370060
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 一般
• Research Field: Biophysics
• Research Institution: Tohoku University
• Principal Investigator: SHIBATA Yutaka 東北大学, 理学(系)研究科(研究院), 准教授 (20300832)
• Co-Investigator(Kenkyū-buntansha): NOGUCHI Takumi 名古屋大学, 大学院理学研究科, 教授 (60241246)
• Research Collaborator: NAMIE Keisuke ; CHIBA Tomofumi ; DU Ting
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: 1分子分光 / 顕微蛍光分光 / 極低温 / 光化学系Ｉ / クラミドモナス

Outline of Final Research Achievements

I developed a cryogenic microscope with a high spatial resolution. Using the developed system, I studied the dynamic movements of the antenna proteins, LHCII, during the state transition, which is a typical light-adaptation function of a green alga, chlamydomonas.
I conducted the single-molecule fluorescence spectroscopy for a photosynthetic protein, photosystem I (PS I). I observed for the first time the blinking of fluorescence from single PS I at around 90 K. I considered the imprecation of this observation for the conformation fluctuation of PS I.
I succeeded in reproducing the temperature dependence of the time-resolved fluorescence spectra of photosystem II using a microscopic model calculation based on the structure.

Free Research Field

生物物理学