Technische Universität Braunschweig, Institute for Physical and Theoretical Chemistry, Department for Biophysical Chemistry, Hans-Sommer-Strasse 10, 38106 Braunschweig, Germany.
J Phys Chem B. 2010 Dec 2;114(47):15650-5. doi: 10.1021/jp1034163. Epub 2010 Nov 9.
Recently, excitonic carotenoid-chlorophyll interactions have been proposed as a simple but effective model for the down-regulation of photosynthesis in plants. The model was proposed on the basis of quenching-correlated electronic carotenoid-chlorophyll interactions (Car S(1) → Chl) determined by Car S(1) two-photon excitation and red-shifted absorption bands. However, if excitonic interactions are indeed responsible for this effect, a simultaneous correlation of quenching with increased energy transfer in the opposite direction, Chl Q(y) → Car S(1), should be observed. Here we present a systematic study on the correlation of Car S(1) → Chl and Chl → Car S(1) energy transfer with the occurrence of red-shifted bands and quenching in isolated LHCII. We found a direct correlation between all four phenomena, supporting our conclusion that excitonic Car S(1)-Chl interactions provide low-lying states serving as energy traps and dissipative valves for excess excitation energy.
最近，激子类胡萝卜素-叶绿素相互作用被提出作为一种简单而有效的模型，用于下调植物中的光合作用。该模型是基于通过 Car S(1) 双光子激发和红移吸收带确定的与猝灭相关的电子类胡萝卜素-叶绿素相互作用（Car S(1) → Chl）提出的。然而，如果激子相互作用确实是造成这种影响的原因，那么在相反方向上同时观察到猝灭与能量转移增加的相关性，Chl Q(y) → Car S(1)，应该被观察到。在这里，我们对在孤立 LHCII 中，Car S(1) → Chl 和 Chl → Car S(1)能量转移与红移带和猝灭的发生之间的相关性进行了系统研究。我们发现了这四个现象之间的直接相关性，这支持了我们的结论，即激子 Car S(1)-Chl 相互作用提供了低能态，作为多余激发能的能量陷阱和耗散阀。
