Division of Material Science (Physics), Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku Nagoya, Aichi 464-8602, Japan.
Langmuir. 2011 Jan 18;27(2):705-13. doi: 10.1021/la1032916. Epub 2010 Dec 20.
An oxygen-evolving photosynthetic reaction center complex (PSII) was adsorbed into nanopores in SBA, a mesoporous silica compound. We purified the dimer of PSII complex from a thermophilic cyanobacterium, Thermosynechococcus vulcanus, which grows optimally at 57 °C. The thermally stable PSII dimeric complex has a diameter of 20 nm and a molecular mass of 756 kDa and binds more than 60 chlorophylls. The SBA particles, with average internal pore diameters of 15 nm (SBA(15)) and 23 nm (SBA(23)), adsorbed 4.7 and 15 mg of PSII/g SBA, respectively. Measurement with a confocal laser-scanning microscope indicated the adsorption of PSII to the surface and the inner space of the SBA(23) particles, indicating the adsorption of PSII into the 23 nm silica nanopores. PSII did not bind to the inner pores of SBA(15). PSII bound to SBA(23) showed the high and stable activity of a photosynthetic oxygen-evolving reaction, indicating the light-driven electron transport from water to the quinone molecules added in the outer medium. The PSII-SBA conjugate can be a new material for photosensors and artificial photosynthetic systems.
一个产氧光合作用反应中心复合物（PSII）被吸附到介孔硅化合物 SBA 的纳米孔中。我们从嗜热蓝藻 Thermosynechococcus vulcanus 中纯化了 PSII 复合物的二聚体，该藻在 57°C 下生长最佳。热稳定的 PSII 二聚体复合物的直径为 20nm，分子量为 756kDa，结合了超过 60 个叶绿素。具有平均孔径为 15nm（SBA(15)）和 23nm（SBA(23)）的 SBA 颗粒分别吸附了 4.7mg 和 15mg PSII/g SBA。共焦激光扫描显微镜的测量表明 PSII 被吸附到 SBA(23)颗粒的表面和内部空间，表明 PSII 被吸附到 23nm 的硅纳米孔中。PSII 未结合到 SBA(15)的内部孔中。与 SBA(23)结合的 PSII 表现出高且稳定的光合放氧反应活性，表明来自水的光驱动电子传递到添加在外介质中的醌分子。PSII-SBA 缀合物可以成为光传感器和人工光合作用系统的新材料。
