Vibrational coherence investigation of protein fluctuations for dynamic allostery

Research Project

Project/Area Number	24657107
Research Category	Grant-in-Aid for Challenging Exploratory Research
Allocation Type	Multi-year Fund
Research Field	Biophysics
Research Institution	The Institute of Physical and Chemical Research
Principal Investigator	KUBO Minoru 独立行政法人理化学研究所, 放射光科学総合研究センター, 専任研究員 (90392878)
Research Collaborator	NAGATOMO Shigenori 筑波大学, 数理物質系化学域, 講師 (80373190)
Project Period (FY)	2012-04-01 – 2015-03-31
Project Status	Completed (Fiscal Year 2014)
Budget Amount *help	¥4,420,000 (Direct Cost: ¥3,400,000、Indirect Cost: ¥1,020,000) Fiscal Year 2014: ¥650,000 (Direct Cost: ¥500,000、Indirect Cost: ¥150,000) Fiscal Year 2013: ¥520,000 (Direct Cost: ¥400,000、Indirect Cost: ¥120,000) Fiscal Year 2012: ¥3,250,000 (Direct Cost: ¥2,500,000、Indirect Cost: ¥750,000)
Keywords	揺らぎ / 振動コヒーレンス / ヘモグロビン / タンパク質 / 低振動 / フェムト秒レーザー / 生体分子分光
Outline of Final Research Achievements	Vibrational coherence spectroscopy was applied to study the correlation between fluctuation of heme and its O2 affinity in hemoglobin (Hb). Damping times of low-frequency coherences (<200 cm-1) of heme, including doming mode coherence, were compared between 5 deoxyHbs with different O2 affinities, regulated by heterotropic effectors. The results showed that the damping times were not correlated with the O2 affinities. Instead, it was confirmed that the Fe-His stretching frequencies were correlated with the O2 affinities. Thus, this study supports Perutz model for the Hb function, although the role of fluctuation of the O2 channel remains to be examined.