Excitonic energy level structure and pigment-protein interactions in the recombinant water-soluble chlorophyll protein. II. Spectral hole-burning experiments.
Excitonic energy level structure and pigment-protein interactions in the recombinant water-soluble chlorophyll protein. II. Spectral hole-burning experiments.
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重组水溶性叶绿素蛋白中的激子能级结构和色素-蛋白质相互作用。
DOI：
10.1021/jp111457t
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发表时间：
2011
期刊：
影响因子：
--
通讯作者：
Gernot Renger
中科院分区：
文献类型：
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作者：
Jörg Pieper;M. Rätsep;I. Trostmann;Franz;C. Theiss;Harald Paulsen;Hans Joachim Eichler;A. Freiberg;Gernot Renger
利用4.5K持续光谱烧孔技术研究了花椰菜重组IIa类水溶性叶绿素结合蛋白（WSCP）的激子能级结构和激发态动力学。烧孔光谱由四个主要特征组成：（i）燃烧波长处的窄零声子空穴（ZPH），（ii）许多振动ZPH，（iii）叶绿素B-和叶绿素a-WSCP分别在~665和~683 nm处的宽低能空穴，以及（iv）叶绿素B-和叶绿素a-WSCP在~658和~673 nm处的第二卫星空穴，分别宽卫星孔的双峰被分配到激子耦合叶绿素二聚体。叶绿素B-和叶绿素a-WSCP在~665和~683 nm处的低能空穴分别代表较低的激子态。考虑到电子-声子耦合的参数，低激子态可以被指定为荧光起源。较低激子态由两个过程填充：（i）从较高激子态的激子弛豫和（ii）较低激子态内的振动弛豫。假设两个激子耦合的叶绿素分子的位置能量相同，基于卫星空穴的位置，叶绿素B-和叶绿素a-WSCP的偶极-偶极相互作用能J分别直接确定为85和100 cm（-1）。在4.5 K下，通过恒注量烧孔实验确定了叶绿素B-和叶绿素a-WSCP的高斯低能吸收带，其宽度约为150 cm（-1），峰值分别位于664.9和682.7 nm。与荧光低激子态相比，其作用光谱更宽且发生蓝移。这一发现可以通过与施密特等人（J.Phys.Chem.B2008，112，13951）的结果一致的最低激子状态内能量不等价的构象亚态之间的缓慢蛋白质弛豫来解释。
Persistent spectral hole burning at 4.5 K has been used to investigate the excitonic energy level structure and the excited state dynamics of the recombinant class-IIa water-soluble chlorophyll-binding protein (WSCP) from cauliflower. The hole-burned spectra are composed of four main features: (i) a narrow zero-phonon hole (ZPH) at the burn wavelength, (ii) a number of vibrational ZPHs, (iii) a broad low-energy hole at ~665 and ~683 nm for chlorophyll b- and chlorophyll a-WSCP, respectively, and (iv) a second satellite hole at ~658 and ~673 nm for chlorophyll b- and chlorophyll a-WSCP, respectively. The doublet of broad satellite holes is assigned to an excitonically coupled chlorophyll dimer. The lower-energy holes at ~665 and ~683 nm for chlorophyll b- and chlorophyll a-WSCP, respectively, represent the lower exciton states. Taking into account the parameters of electron-phonon coupling, the lower exciton state can be assigned as the fluorescence origin. The lower exciton state is populated by two processes: (i) exciton relaxation from the higher exciton state and (ii) vibrational relaxation within the lower exciton state. Assuming identical site energies for the two excitonically coupled chlorophyll molecules, the dipole-dipole interaction energy J is directly determined to be 85 and 100 cm(-1) for chlorophyll b- and chlorophyll a-WSCP, respectively, based on the positions of the satellite holes. The Gaussian low-energy absorption band identified by constant fluence hole burning at 4.5 K has a width of ~150 cm(-1) and peaks at 664.9 and 682.7 nm for chlorophyll b- and chlorophyll a-WSCP, respectively. The action spectrum is broader and blue-shifted compared to the fluorescent lower exciton state. This finding can be explained by a slow protein relaxation between energetically inequivalent conformational substates within the lowest exciton state in agreement with the results of Schmitt et al. (J. Phys. Chem. B2008, 112, 13951).
来自甘蓝的重组水溶性叶绿素蛋白。
DOI：
--
发表时间：
2003
期刊：
Biochemistry 42
影响因子：
--
作者：
Christiane Reinbothe;Hiroyuki Satoh;Jean-Pierre Alcaraz;Steffen Reinbothe;K.Schmidt et al.
通讯作者：
K.Schmidt et al.