NBS修饰^(241)Trp对33kD外周蛋白与PSⅡ的结合及放氧活性恢复的影响  

The Influence of NBS Modification of 241 Trp on the Reconstitution of 33 kD Protein with PSⅡand on the Recovery of Oxygen evolving Activity

作　　者：于勇[1,2] 李荣 田少敏[1,2] 徐春和 阮康成[1,2] 

机构地区：[1]中国科学院上海植物生理研究所 [2]中国科学院上海生物化学研究所

出　　处：《生物化学与生物物理学报》1999年第3期341-343,共3页

基　　金：国家自然科学基金;国家重点基础研究发展规划资助项目

摘　　要：高等植物光系统Ⅱ（ＰＳⅡ）中膜结合的３３ｋＤ外周蛋白对锰分子簇的稳定及ＰＳⅡ高放氧活力的维持具有重要意义。本文通过ＮＢＳ对菠菜３３ｋＤ蛋白中唯一的色氨酸残基（近Ｃ端２４１Ｔｒｐ）的修饰研究了该残基在光合放氧系统中的作用。结果表明２４１Ｔｒｐ位于３３ｋＤ蛋白内部的疏水区。修饰后的３３ｋＤ外周蛋白对ＰＳⅡ颗粒的重组能力减弱。部分重组上经ＮＢＳ修饰的３３ｋＤ蛋白的ＰＳⅡ颗粒放氧活力得不到恢复。表明２４１Ｔｒｐ对３３ｋＤ蛋白与ＰＳⅡ的结合及功能的实现有着特殊意义。The extrinsic 33 kD protein of photosystemⅡ(PSⅡ) plays an important role in the stabilizing of manganese cluster and maintaining high oxygen evolving activity of PSⅡ. In this research, 241 Trp, the only tryptophan in the 33 kD protein, was modified by N Bromosuccinimide. The pH dependence of modification suggests that this tryptophan is buried in the hydrophobic interior of the protein. The protein's capability of reconstitution to the PSⅡdecreased after modification, and no oxygen evolving activity of PSⅡwas recovered after the reconstitution. Results suggest that 241 Trp of the 33 kD protein is essential for the binding of the protein to the PSⅡand the normal oxygen evolving activity.

关 键 词：33kD外周蛋白 色氨酸 化学修饰 PSⅡ 放氧 

分 类 号：Q946.13[生物学—植物学]