【摘要】 将分离纯化的菠菜光系统ⅡD1-D2-Cytb559反应中心复合物和33kD外周蛋白按摩尔比1∶1或2∶1的比例进行体外重组,监测重组过程中的室温可见光区吸收光谱和荧光发射光谱的变化。结果表明:重组过程中,样品的室温可见光区吸收光谱几乎无变化,但室温荧光发射光谱却有明显的变化,蛋白质内源荧光和叶绿素荧光的强度都有先增加后降低的现象,暗示33kD蛋白与D1-D2-Cytb559复合物在形成稳定的重组复合物之前,存在一个复杂的蛋白构象变化过程,重组时33kD蛋白与反应中心复合物的结合,可能影响了反应中心D1或D2色素蛋白所结合的叶绿素a等色素分子的微环境。更多还原

【Abstract】 T he 33 kD protein and the PSⅡreaction center D1-D2-Cyt b559 complex were isolated from photosystem Ⅱparticles of spinach (Spinacia oleracea L) respectively, then they were reconstituted according two kinds of propo rtion (33 kD protein∶reaction center = 1∶1/ 2∶1). The absorption spect ra and the fluorescence spectra of the reconstitution mixture were inv estigated during the reconstitution progress at room temperature. The r esults showed that no changes of the absorption spectra of the reacti on mixture were observed, however, the fluorescence emission spectra al tered markedly. The fluorescence emission maximum either excited at 278 or 295 and 436 nm increased firstly, then decreased. The results sugge sted that the reconstitution reaction is a complicated process and the binding of 33 kD protein to PSⅡreaction center D1-D2-Cyt b559 comple x may affect the microenvironment of chlorophyll a molecular in the D 1 or D2 protein.更多还原