摘要
研究了冷害温度(0℃,16h)对黄瓜(Cucumis sativus L.)叶绿体类囊体膜膜脂、膜蛋白成分的影响。在没有可见伤害症状的低温处理条件下,黄瓜叶片叶绿体类囊体膜膜脂成分已有变化,主要是磷脂酰甘油(PG)含量明显降低,但主要脂类成分单半乳糖基甘油二酯(MGDG)、双半乳糖基甘油二酯(DGDG)、硫代异鼠李糖甘油二酯(SQDC)和PG的脂肪酸组分没有明显的变化;类囊体膜上色素蛋白质复合体的变化以光系统Ⅱ捕光叶绿素a/b蛋白质(LHCⅡ)单体及寡聚体含量的变化最明显,低温处理使LHCⅡ单体比例增加。对提纯的LHCⅡ结合脂的分析表明,低温处理改变了LHCⅡ结合脂及其脂肪酸的组成,使PG含量降低。以上结果表明,LHCⅡ结合脂成分变化以及LHCⅡ寡聚体解聚可能是叶绿体类囊体膜受冷害的最初反应。
Some changes in the components of cucumber ( Cuciurds sativus L.) thylakoid membrane occurred before any visible chilling injury appeared when cucumber leaves were treated with chilling temperature (0 ℃ , 16 h). Chilling temperature induced a specific decrease of phosphatidyl glycerol (PG) content accompanied with an increase of PS Ⅱ light-harvesting chlorophyll a/b-protein complex (LHCⅡ ) monomer content and a decrease of LHC Ⅱ oligomer content in the thylakoid membrane . It also had a significant effect on the content of lipids and the fatty acid composition of each of lipid class of purified LHC Ⅱ . The PG content decreased obviously and the content of other lipid classes increased. The fatty acid composition of each lipid class from purified LHC Ⅱ was also affected . The results suggested that the changes in PG content and LHC Ⅱ supermolecular structure might be the primary indications of chilling injury.
关键词
冷害
类囊体膜
黄瓜
叶绿体
Chilling injury, Thylakoid membrane, Membrane lipids, Membrane protein
