In photosynthesis, the antenna system captures solar energy and transfers the excitations to photosystem II (PSII) core complex where charge separation, water splitting and oxygen evolution occur. In the evolution of photosynthesis from aquatic to terrestrial environments, the structure of PSII core complex was highly conserved while a variety of antenna forms became differentiated. In order to study the principles for energy transport from antenna to the PSII reaction center, we have explored whether the major light harvesting complex of PSII (LHCII) of higher plants can transfer energy to the cyanobacteria PSII core complexes (CC). For this purpose, LHCII from pea and CC from Thermosynechococcus vulcanus were isolated and co-reconstituted into liposome at LHCII:CC molar ratios of 2:1, 4:1 and 6:1, respectively. Chemical-cross linking followed by LC-MS/MS analysis confirmed the biochemical interaction between LHCII and CC in the liposome membrane. The analyses of 77 K fluorescence emission spectra and antenna cross section of PSII indicated that LHCII can transfer energy directly to the cyanobacterial CC. The study has laid the basis for further research on the mechanism of energy transfer from LHCII to PSII CC. This result may also open a new possibility for design and development of new artificial PSII in the application of solar energy conversion.

在光合作用中，天线系统捕获太阳能并将激发转移到光系统II（PSII）核心复合体，在此发生电荷分离，水分解和氧气释放。在从水生环境到陆地环境的光合作用演变过程中，PSII核心复合物的结构高度保守，同时区分了多种天线形式。为了研究从天线到PSII反应中心的能量传输原理，我们探讨了高等植物PSII的主要光收集复合体（LHCII）是否可以将能量转移至蓝细菌PSII核心复合体（CC）。为此，来自豌豆的LHCII和来自Thermosynechococcus vulcanus的CC分别以2：1、4：1和6：1的LHCII：CC摩尔比分离并共重构为脂质体。化学交联后再进行LC-MS / MS分析，证实了脂质体膜中LHCII和CC之间的生化相互作用。对PSII的77 K荧光发射光谱和天线横截面的分析表明，LHCII可以将能量直接传递给蓝细菌CC。该研究为进一步研究从LHCII到PSII CC的能量转移机理奠定了基础。这一结果也可能为在太阳能转换应用中设计和开发新型人工PSII开辟新的可能性。