Prokhorenko V I, Steensgaard D B, Holzwarth A R
Max-Planck-Institut für Strahlenchemie, D-45413, Mülheim a.d. Ruhr, Germany.
Biophys J. 2000 Oct;79(4):2105-20. doi: 10.1016/S0006-3495(00)76458-7.
The energy transfer processes in isolated chlorosomes from green bacteria Chlorobium tepidum and Chloroflexus aurantiacus have been studied at low temperatures (1.27 K) by two-pulse photon echo and one-color transient absorption techniques with approximately 100 fs resolution. The decay of the coherence in both types of chlorosomes is characterized by four different dephasing times stretching from approximately 100 fs up to 300 ps. The fastest component reflects dephasing that is due to interaction of bacteriochlorophylls with the phonon bath, whereas the other components correspond to dephasing due to different energy transfer processes such as distribution of excitation along the rod-like aggregates, energy exchange between different rods in the chlorosome, and energy transfer to the base plate. As a basis for the interpretation of the excitation dephasing and energy transfer pathways, a superlattice-like structural model is proposed based on recent experimental data and computer modeling of the Bchl c aggregates (1994. Photosynth. Res. 41:225-233.) This model predicts a fine structure of the Q(y) absorption band that is fully supported by the present photon echo data.
利用具有约100飞秒分辨率的双脉冲光子回波和单色瞬态吸收技术，在低温（1.27K）下研究了来自嗜热绿菌和橙色绿屈挠菌的分离的叶绿体中的能量转移过程。两种类型的叶绿体中相干性的衰减具有四个不同的退相时间，范围从约100飞秒到300皮秒。最快的成分反映了由于细菌叶绿素与声子浴相互作用引起的退相，而其他成分则对应于由于不同能量转移过程引起的退相，例如激发沿棒状聚集体的分布、叶绿体中不同棒之间的能量交换以及能量转移到底板。作为解释激发退相和能量转移途径的基础，基于最近的实验数据和Bchl c聚集体的计算机建模（1994年。光合作用研究。41:225 - 233）提出了一种超晶格状结构模型。该模型预测了Q(y)吸收带的精细结构，这得到了当前光子回波数据的充分支持。
