【摘要】 选取野生型莱茵衣藻CC-125和过氧化氢酶缺失突变体CC-2913为研究对象,采用spintrapping-ESR方法通过光照莱茵衣藻类囊体膜捕获到了O2·-,并且在同样条件下也检测到了来源于O2·-歧化产生的H2O2。另据类囊体膜电泳实验结果:莱茵衣藻在生长过程中添加内源SOD抑制剂TCNE后,CC-2913类囊体膜光系统蛋白组分的损伤要比野生型CC-125更为严重。通过对上述O2·-与H2O2信号的对比分析可知,虽然O2·-不是造成类囊体膜光系统Ⅱ蛋白组分损伤的直接因素,但它可借助歧化产物H2O2造成光系统蛋白组分的损伤。更多还原

【Abstract】 Photoinitiated superoxide anion radical (O2·-) has been examined in thylakoid membranes isolated from Chlamydomonas reinhardtii wild-type strains CC-125 and catalase-deficient mutant CC-2913, by spin trapping-ESR. Concentration of hydrogen peroxide (H2O2), produced from disproportionation of O2·-, was monitored by hydrogen peroxide sensor (ISO- HPO-2) under identical conditions. Urea-SDS-PAGE of thylakoid membranes further demonstrated that upon the addition of intrinsic SOD inhibitor tetracyanethylen (TCNE), ROS caused more damage to PSII components of CC-2913 than that of wild-type CC-125. It is concluded by comparing H2O2 and O2·-, that although the original O2·- didn’t directly cause damage to PSII components, the subsequently produced H2O2 could trigger obvious damage to the PSII component proteins.更多还原