Coherent dynamics and ultrafast excited state relaxation of blue copper protein; plastocyanin.
Coherent dynamics and ultrafast excited state relaxation of blue copper protein; plastocyanin.
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蓝铜蛋白的相干动力学和超快激发态弛豫；
DOI：
10.1039/b926518j
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发表时间：
2010
期刊：
影响因子：
--
通讯作者：
S. Hirota
中科院分区：
文献类型：
--
作者：
Y. Nagasawa;K. Fujita;Tetsuro Katayama;Y. Ishibashi;H. Miyasaka;T. Takabe;S. Nagao;S. Hirota
在飞秒到皮秒的时间范围内，对蓝铜蛋白--质蓝蛋白(Pc)进行了超快瞬时吸收测量。为了比较光激发后配体-金属电荷转移(LMCT)带和d-d跃迁带的动力学分布，分别将泵浦波长设置为597 nm和895 nm。结果基本一致，表明从LMCT态到低配位场(LF)态的转变发生在小于40fs的超快时间范围内。随后，在LF态发生驰豫，时间常数为90ps，系统返回到基态，时间常数为250fS。最大时间常数为1.8ps归因于基态的振动冷却。观察到几种波包运动，包括约510 nm处的Franck-Condon型运动和660-720 nm处的Herzberg-Teller型运动。两个激发波长的最大振幅都在600 nm附近，还观察到了约30 cm(-1)的严重衰减的低频振荡。这种振荡可能是由于超快松弛对蛋白质的弹道刺激造成的。
Ultrafast transient absorption measurements in the femtosecond to picosecond time region were carried out for a blue copper protein, plastocyanin (Pc). To compare the dynamical profiles after photoexcitation upon the ligand-to-metal-charge-transfer (LMCT) band and the d-d transition band, the pump wavelength was set at wavelengths of 597 and 895 nm, respectively. The results were nearly identical, indicating that the transition from the LMCT to the lower ligand field (LF) states takes place in an ultrafast time regime of less than 40 fs. Subsequently, relaxation in the LF state occurs with a time constant of 90 fs and the system returns to the ground state with that of 250 fs. The longest time constant of 1.8 ps was attributed to the vibrational cooling in the ground state. Several wavepacket motions were observed, including Franck-Condon type motion at approximately 510 nm and a Herzberg-Teller type motion at 660-720 nm. Critically damped low-frequency oscillation of approximately 30 cm(-1) was also observed with both excitation wavelengths with the strongest amplitude around 600 nm. This oscillation could be due to the motion of the protein that is ballistically stimulated by ultrafast relaxation.
影响因子：
56.9
作者：
SOLOMON, EI;LOWERY, MD
通讯作者：
LOWERY, MD