PHOTODAMAGE OF PHOTOSYSTEM I REACTION CENTER D_1-D_2-CYTOCHROME B_558 COMPLEX
光系统Ⅱ反应中心D_1-D_2-Cyt b_(559)的光破坏作用研究

Photosystem I reaction center D1-D2-Cytochrome b550 purified from high plant was damaged very easily by illumination. During initial 30S of light treatment, the absorbance increased. Following the process of absorbance increasing, continuing illumination led to the decrease of absorbance, blue-shifting of absorption maximum wavelength at red absorption region. Illumination also gave rise to increase of fluorescence emission intensity and blue-shifting of emission maximum wavelength. These results show that there may be two different processes of photodamaging to photosystem I reaction center and P680 is most sensitive to light treatment.