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植物光系统Ⅱ反应中心Ｄ２多肽第１６０位酪氨酸残基（Ｙ_Ｄ）氧化可以产生电子顺磁共振（ＥＰＲ）信号 Ｓｉｇｎａｌ Ⅱ_（ｓｌｏｗ．）高浓度的三氯乙酸盐（ＴＣＡ）短时间处理莱因衣藻（Ｃｈｌａｍｙｄｏｍｏｎａｓ ｒｅｉｎｈａｒｄｔｉｉ）类囊体可以直接促使氧化态的 Ｙ_Ｄ（Ｙ_Ｄ）迅速还原，淬灭 Ｓｉｇｎａｌ Ⅱ_（ｓｌｏｗ·）这种作用具有浓度和时间效应．ＴＣＡ处理引起类囊体膜上包括３个放氧外周多肽在内的部分多肽脱落．在衣藻光系统Ⅱ反应中心三维分子模型的基础上对Ｙ_Ｄ周围的氨基酸微环境进行了分析，认为Ｙ_Ｄ周围相对较强的疏水性微环境可能是 ＴＣＡ影响 Ｙ_Ｄ氧化还原状态的前提．同时， ＴＣＡ处理还能稳定源于光系统 Ⅰ中氧化态的反应中心色素双分子 Ｐ_（７００）~＋的 ＥＰＲ信号 Ｓｉｇｎａｌ Ⅰ，抑制其衰减．
Plant photo-system Ⅱ reaction center D2 polypeptide tyrosine residue (Y_D) oxidation can generate electronic paramagnetic resonance (EPR) Signal Ⅱ slow () TCA high concentration of short-term treatment Chlamydomonas reinhardtii thylakoid can directly promote the rapid oxidation of Y_D (Y_D), quenching Signal Ⅱ slow (slow) This effect has a concentration and time effect. TCA treatment caused partial shedding of part of the polypeptide on the thylakoid membrane including the three oxygen-releasing peripheral polypeptides. Amino acid microenvironment around Y_D was analyzed on the basis of three-dimensional molecular model of Chlamydomonone system Ⅱ reaction center. It is considered that the relatively strong hydrophobic microenvironment around Y_D may be the premise of TCA affecting Y_D redox state. At the same time, the TCA treatment can also stabilize signal EPR signal Signal Ⅰ, which is derived from the reaction center pigment biomolecule P_ (700) ~ + in the oxidation state Ⅰ, and attenuates its attenuation.