|Budget Amount *help
¥121,550,000 (Direct Cost: ¥93,500,000、Indirect Cost: ¥28,050,000)
Fiscal Year 2005: ¥12,220,000 (Direct Cost: ¥9,400,000、Indirect Cost: ¥2,820,000)
Fiscal Year 2004: ¥21,320,000 (Direct Cost: ¥16,400,000、Indirect Cost: ¥4,920,000)
Fiscal Year 2003: ¥21,450,000 (Direct Cost: ¥16,500,000、Indirect Cost: ¥4,950,000)
Fiscal Year 2002: ¥30,680,000 (Direct Cost: ¥23,600,000、Indirect Cost: ¥7,080,000)
Fiscal Year 2001: ¥35,880,000 (Direct Cost: ¥27,600,000、Indirect Cost: ¥8,280,000)
A variety of experimental techniques to monitor the time dependence of the thermodynamical quantities have been developed. These techniques have been used to elucidate protein reaction dynamics and some results are listed below.
1. After the photoexcitation of myoglobin, energetic relaxation pathway and the ligand escaping process from the protein interior to the solvent were studied by the time-resolved transient grating technique. The energy landscape for the ligand dissociation reaction was determined by using site directed mutants. It was found that the protein fluctuation is important for inducing the ligand escape. Furthermore, the ligand escape routes inside the protein were clearly determined by using the Xe pressure dependence of the escaping rate.
2. The energy landscape and volume change were determined for the photoreaction of octopus rhodopsin. A new reaction intermediate was discovered as the change in the protein volume. The determined energy landscape in this reaction is the first example of the experimentally determined energy surface during chemical reactions.
3. The protein fluctuation for intermediate species of Photoactive Yellow Protein (PYP) was experimentally observed for the first time. It was found that the subsequent thermal reaction of PYP is induced by this fluctuation. The molecular diffusion of the intermediate of PYP was discussed in detail.
4. It was found that the diffusion coefficients of proteins reflect conformations in solution and the time-dependence of the coefficient was measured for the first time in science. This technique was applied to protein folding research of cytochrome c. The time evolution of the hydrogen bonding during the protein folding reaction was elucidated.