摘要
以高等植物大量捕光色素蛋白复合物(major light harvesting complexⅡ,LHCⅡb)对光系统Ⅱ(photosystemⅡ,PSⅡ)放氧活性的影响为研究对象,从豌豆类囊体膜中分步提取出三种PSⅡ蛋白复合物,结合电泳和光谱分析,鉴定出三种复合物的主要区别是LHCⅡb含量不同。对于三种PSⅡ色素蛋白复合物在不同光质和光强下放氧速率变化的测定结果表明,三种复合物的放氧速率均存在光饱和点。含有1～2个LHCⅡb三体的粗核心提取物的放氧活性和几乎不含LHCⅡb的纯核心的放氧活性一致,但是它们的放氧活性都远低于含有5～6个LHCⅡb三体的富含PSⅡ颗粒的膜片。说明PSⅡ超分子体系在少于2个外周天线时不能发挥正常的光化学活性。
Three different types of photosystem Ⅱ（PSⅡ） preparations,PSⅡ enriched membranes,PSⅡ crude core particles and PSⅡ core complexes,were isolated from thylakoid membranes of pea seedlings.The structural analysis showed that the main difference among the preparations was the size of the antenna cross section in the PSⅡ macrostructure.The functional analysis to different PSⅡ preparations showed that the oxygen evolution from PSⅡ enriched membranes,containing 5～6 LHCⅡb trimers per PSⅡ dimmer,was about three times higher than those of PSⅡ particle preparation（containing 1～2 LHCⅡb） and the PSⅡ core complexes（containing almost no LHCⅡb）.Comparing the differences among the three PSⅡ preparations reveals that the attachment of more than 2 trimeric LHCⅡb is the prerequisite for the perfect functionality of PSⅡ supercomplexes.
出处
《生物物理学报》
CAS
CSCD
北大核心
2011年第2期127-134,共8页
Acta Biophysica Sinica
基金
国家自然科学基金项目(71070212)
"973"计划项目(2009cb118501)~~
关键词
光系统Ⅱ
大量捕光色素蛋白复合物
放氧速率
Photosystem Ⅱ
Major light-harvesting chlorophyⅡ a/b complexe of photosystem Ⅱ
Oxygen evolution rate
