Laboratory of Molecular Biophysics


Toshimichi FUJIWARA
Associate Professor
Chojiro KOJIMA
Associate Professor
Takahisa IKEGAMI
Assistant Professor
Yoh Matsuki

Structual Infomation Biology


Institute for Protein Research


Suita Campus

Research Theme

Signal transduction and energy conversion play very important roles in the human body. Many these functions are performed by supramolecular systems across biomembranes. These systems are also responsible for forming networks for integrated biological activities. Reports on structures of these systems increase rapidly in number recently. We are elucidating these important functions of proteins on the basis of structures revealed by NMR (Nuclear Magnetic Resonance).

Structural and functional studies of protein by solid-state NMR

Solid-state NMR reveals structure and function of biologically important molecular complexes that are not amenable to X-ray crystallography and solution NMR. These systems include proteins tightly bound to lipid bilayers and noncrystalline large molecular complexes. For example, we study membrane protein pHtrⅡ for the transmission of light signal, transmembrane domains of proton ATP synthase, and model G-protein-receptor complexes. We are also developing NMR methods by using advanced technologies for NMR experiments, molecular biology and bioinformatics.

Structural and functional studies of protein by solution NMR

Dynamical protein structures can be determined at atomic resolution by NMR. We study protein-protein and protein-ligand interactions as well as monomer structures. These interactions often correlate with slow molecular motions on us-ms time scales. We are further developing methods for investigating activity-dynamics relationships that are still immature.

Research subjects

1. Structure of membrane protein pHtrⅡ for transmitting light signal 2. Structure of halorhodopsin relevant for light-driven ion pumping 3. Protein-protein interactions for clock and signal transduction 4. Signal transduction through biomembranes by G-protein activating peptides 5. Functional slow protein motions revealed by NMR relaxation 6.Structure analysis by NMR bioinformatics 7. Application of NMR with enhanced sensitivity by terahertz waves

0Signal transduction by way of membrane proteins

1NMR magnet and high-intensity terahertz light source


E. Harada, Y. Todokoro, H. Akutsu, and T. Fujiwara. Detection of Peptide−Phospholipid Interaction Sites in Bilayer Membranes by 13C-NMR Spectroscopy: Observation of 2H/31P-Selective 1H-Depolarization under Magic-Angle Spinning J. Am. Chem. Soc. 128 , 10654 - 10655 (2006)

A. Egawa, T. Fujiwara, T. Mizoguchi, Y. Kakitani, Y. Koyama, and H. Akutsu Structure of the Light-Harvesting Bacteriochlorophyll c Assembly in Chlorosomes from Chlorobium Limicola Determined by Solid-State NMR Proc. Natl. Acad. Sci. U.S.A. 104 , 790 - 795 (2007)

Masatoshi Kobayashi, Andrey V. Struts, Toshimichi Fujiwara, Michael F. Brown, Hideo Akutsu Fluid Mechanical Matching of H+-ATPsynthase Subunit c Ring with Lipid Membranes Revealed by 2H Solid-State NMR Biophys. J. 94 , 4339 - 4347 (2008)

Yoh Matsuki, Hiroki Takahashi, Keisuke Ueda, Toshitaka Idehara, Isamu Ogawa, Mitsuru Toda, Hideo Akutsu and Toshimichi Fujiwara Dynamic Nuclear Polarization Experiments at 14.1 T for Solid-State NMR Phys. Chem. Chem. Phys. DOI:10.1039/c002268c , (2010)

Hideo Akutsu, Ayako Egawa, Toshimichi Fujiwara Atomic structure of the bacteriochlorophyll c assembly in intact chlorosomes from Chlorobium limicola determined by solid-state NMR Photosynth. Res. DOI: 10.1007/s11120-009-9523-2 , (2010)


Institute for Protein Research, Osaka University
3-2 Yamadaoka, Suita, Osaka 565-0871, Japan
Tel +81-6-6879-8598 Fax +81-6-6879-8599