Femtosecond infrared spectroscopy of chlorophyll f-containing photosystem I.
Femtosecond infrared spectroscopy of chlorophyll f-containing photosystem I.
复制标题
含叶绿素 f 的光系统 I 的飞秒红外光谱。
DOI：
10.1039/c8cp05627g
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发表时间：
2019
期刊：
影响因子：
--
通讯作者：
Zamzam N
中科院分区：
文献类型：
--
作者：
Zamzam N
The recent discovery of extremely red-shifted chlorophyll f pigments in both photosystem I (PSI) and photosystem II has led to the conclusion that chlorophyll f plays a role not only in the energy transfer, but also in the charge separation processes [Nürnberg et al., Science, 2018, 360, 1210–1213]. We have employed ultrafast transient infrared absorption spectroscopy to study the contribution of far-red light absorbing chlorophyll f to energy transfer and charge separation processes in far-red light-grown PSI (FRL-PSI) from the cyanobacterium Chroococcidiopsis thermalis PCC 7203. We compare the kinetics and spectra of FRL-grown PSI excited at 670 nm and 740 nm wavelengths to those of white light-grown PSI (WL-PSI) obtained at 675 nm excitation. We report a fast decay of excited state features of chlorophyll a and complete energy transfer from chlorophyll a to chlorophyll f in FRL-PSI upon 670 nm excitation, as indicated by a frequency shift in a carbonyl absorption band occurring within a 1 ps timescale. While the WL-PSI measurements support the assignment of initial charge separation to A−1+˙A0−˙ [Di Donato et al., Biochemistry, 2011, 50, 480–490] from the kinetics of a distinct cation feature at 1710 cm−1, in the case of FRL-PSI, small features at 1715 cm−1 from the chlorophyll cation are present from sub-ps delays instead, supporting the replacement of the A−1 pigment with chlorophyll f. Comparisons of nanosecond spectra show that charge separation proceeds with 740 nm excitation, which selectively excites chlorophyll f, and modifications in specific carbonyl absorption bands assigned to P700+˙ minus P700 and A1−˙ minus A1 indicate dielectric differences of FRL-PSI compared to WL-PSI in one or both of the two electron transfer branches of FRL-PSI.
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影响因子：
3.8
作者：
Kaucikas, M.;Barber, J.;Van Thor, J. J.
通讯作者：
Van Thor, J. J.
影响因子：
2.9
作者：
Di Donato, Mariangela;Stahl, Andreas D.;Groot, Marie-Louise
通讯作者：
Groot, Marie-Louise
蓝藻光系统 I 中的电子转移
影响因子：
4.8
作者：
Wu Xu;P. Chitnis;Alfia I Valieva;A. van der Est;K. Brettel;M. Guergova;Y. Pushkar;S. Zech;D. Stehlik;G. Shen;B. Zybailov;J. Golbeck
通讯作者：
J. Golbeck
影响因子：
2.9
作者：
Joliot, P;Joliot, A
通讯作者：
Joliot, A
光系统 I 反应中心中电荷分离和 A0- --> A1 电子转移的动力学。
影响因子：
2.9
作者：
S. Savikhin;W. Xu;P. Martinsson;P. Chitnis;W. Struve
通讯作者：
W. Struve