Optically Matched Semiconductor Quantum Dots Improve Photophosphorylation Performed by Chloroplasts

A natural–artificial hybrid system was constructed to enhance photophosphorylation. The system comprises chloroplasts modified with optically matched quantum dots (chloroplast–QD) with a large Stokes shift. The QDs possess a unique optical property and transform ultraviolet light into available and highly effective red light for use by chloroplasts. This favorable feature enables photosystem II contained within the hybrid system to split more water and produce more protons than chloroplasts would otherwise do on their own. Consequently, a larger proton gradient is generated and photophosphorylation is improved. At optimal efficiency activity increased by up to 2.3 times compared to pristine chloroplasts. Importantly, the degree of overlap between emission of the QDs and absorption of chloroplasts exerts a strong influence on the photophosphorylation efficiency. The chloroplast–QD hybrid presents an efficient solar energy conversion route, which involves a rational combination of a natural system and an artificial light‐harvesting nanomaterial.     

LaCl3和PrCl3对菠菜离体叶绿体光合磷酸化作用的影响

LaCl3，PrCl3对离体叶绿体的FeCy光还原活性，随La^3 ，Pr^3 浓度递增而增高，动力学曲线明显呈S形；LaCl3，PrCl3处理叶绿体后，能促进循环( PMS)和非循环( FeCy或MV)光合磷酸化反应，提高叶绿体的偶联程度，增加ADP／O及PC比值，对叶绿体膜上的Mg^2 -ATP酶及偶联因子Ca^2 -ATP酶活力有一定激活作用。这表明LaCl3，PrCl3促进光合作用可能与激活偶联因子活性有关。