One electron paramagnetic resonance(EPR)signal,named SignalⅡslow,originates from the oxidized Tyrosine 160(Y_(D))of D2 polypeptide of photosystemⅡreaction center.After adding high concentration trichloroacetate(TCA)...One electron paramagnetic resonance(EPR)signal,named SignalⅡslow,originates from the oxidized Tyrosine 160(Y_(D))of D2 polypeptide of photosystemⅡreaction center.After adding high concentration trichloroacetate(TCA)to the Chlamydomonas reinhardtii thylakoid suspension.this signal was abolished in a minute.Treatment of TCA also removes a few of polypeptides,including three extrinsic polypeptides of oxygen-evolving complex,from the thylakoid membrane.Based upon the analysis of the microenvironment around YD with a three-dimensional model,it is indicated that relatively high hydrophobicity of this microenvironment may be the essential prerequisite for TCA to affect YD.It has been observed that TCA treatment also retards the decay of the Signal I,produced by the oxidized reaction center chlorophyll dimer(P700^(+))of photosys-tem I.展开更多
基金This work was supported by the State Key Bausic Research and Developmen Plan(Grant No.G1998010100)the National Natural Science Foundation of China(Grant No.39730040).
文摘One electron paramagnetic resonance(EPR)signal,named SignalⅡslow,originates from the oxidized Tyrosine 160(Y_(D))of D2 polypeptide of photosystemⅡreaction center.After adding high concentration trichloroacetate(TCA)to the Chlamydomonas reinhardtii thylakoid suspension.this signal was abolished in a minute.Treatment of TCA also removes a few of polypeptides,including three extrinsic polypeptides of oxygen-evolving complex,from the thylakoid membrane.Based upon the analysis of the microenvironment around YD with a three-dimensional model,it is indicated that relatively high hydrophobicity of this microenvironment may be the essential prerequisite for TCA to affect YD.It has been observed that TCA treatment also retards the decay of the Signal I,produced by the oxidized reaction center chlorophyll dimer(P700^(+))of photosys-tem I.
