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用强光（光强为２３００μｍｏｌ·ｍ－２· ｓ－１）对菠菜（Ｓｐｉｎａｃｉａ Ｏｌｅｒａｃｅａ Ｌ．）叶绿体中分离提纯的ＰＳＩ颗粒进行不同时间的光照处理，通过分析其光谱特性的变化，以及利用 ＳＤＳ－ＰＡＧＥ技术分析其多肽组成的变化，研究了 ＰＳＩ颗粒中色素和多肽组分的光破坏过程．发现 ＰＳＩ颗粒中叶绿素对强光处理的敏感性不仅同所处的能级有关，还同它所结合的位置有关．在 ＰＳＩ颗粒叶绿素中长波吸收组分首先发生光破坏，同时位于颗粒外围的外周天线色素蛋白复合物 ＬＨＣＩ上的叶绿素 ｂ也容易受到光破坏．光照处理过程中， ＬＨＣⅠ多肽降解程度大于反应中心多肽组分（６６， ６７ ｋｕ）的降解． ＰＳＩ中其他一些多肽对强光也较反应中心多肽敏感，其中 ＬＨＣＩ－６８０多肽组分（Ｌｈｃａ３，Ｌｈｃａ ２）和ＰｓａＤ最先发生光破坏．另外，还发现在长时间光照后有蛋白聚合现象出现．
The PSI particles isolated and purified from chloroplasts of spinach (Spinacia Oleracea L.) were treated with light at a light intensity of 2300μmol · m-2 · s-1 for different time periods. The changes of spectral properties were analyzed by SDS -PAGE technology analysis of changes in the composition of the polypeptide to study PSI particles in the pigment and polypeptide components of the light damage process. It was found that the sensitivity of PSI particles to glare treatment is not only related to the energy level at which they are located, but also to the location at which they bind. The long-wave absorption component of PSI particle chlorophyll firstly photo-destroyed, and the chlorophyll b located on LHCI, which is located on the outer periphery of the particle periphery, was also easily damaged by light. During the light treatment, the degradation of LHC Ⅰ polypeptide was more than that of the reaction center polypeptide (66, 67 ku). Other peptides in PSI were also more sensitive to light than the reaction center polypeptide, of which LHCI-680 polypeptide components (Lhca3, Lhca 2) and PsaD first light-induced damage. In addition, it was also found that protein aggregation occurred after a long time of illumination.