Khristin M S, Simonova N B
Institute of Soil Science and Photosynthesis, Russian Academy of Sciences, Pushchino, Moscow Region, Russia.
Membr Cell Biol. 1998;12(1):57-66.
Effects of glycerol on the extraction efficiency and the stability of pigment-protein complexes (PPC) of photosystem 2 (PS2) from membranes of the green unicellular alga Dunaliella salina were studied. PS2 membranes were extracted with the detergent n-dodecyl-beta-maltoside (DM) in the presence of 4 M glycerol and 1 M NaCl at a DM:chlorophyll ratio of 15:1 (w/w). The extracts were purified on a DEAE fractogel 650S column. To assess the effect of glycerol on the PPC stability, PS2 membranes were illuminated with white light of high intensity. Then PPCs were extracted and studied spectroscopically and using PAG electrophoresis under denaturing and native conditions. It was found that addition of 4 M glycerol and 1 M NaCl to the extraction medium affects the extraction of the PS2 PPCs but not of the light-harvesting chlorophyll a/b protein (LH2). It was shown that 4 M glycerol protects PS2 from the destructive effects of intense white light, high NaCl concentration, and the detergent Triton X-100. It is suggested that, apart from its osmotic action, glycerol performs a protective function and stabilizes PS2 PPCs in the cells of Dunaliella salina.
研究了甘油对绿色单细胞藻类杜氏盐藻（Dunaliella salina）膜中光系统2（PS2）色素 - 蛋白质复合物（PPC）提取效率和稳定性的影响。在4 M甘油和1 M氯化钠存在下，以洗涤剂正十二烷基 - β - 麦芽糖苷（DM）按DM：叶绿素比例15：1（w/w）提取PS2膜。提取物在DEAE fractogel 650S柱上进行纯化。为了评估甘油对PPC稳定性的影响，用高强度白光照射PS2膜。然后提取PPC，并在变性和天然条件下通过光谱学和聚丙烯酰胺凝胶电泳（PAG）进行研究。结果发现，在提取介质中添加4 M甘油和1 M氯化钠会影响PS2 PPC的提取，但不影响捕光叶绿素a/b蛋白（LH2）的提取。结果表明，4 M甘油可保护PS2免受强光、高氯化钠浓度和洗涤剂Triton X - 100的破坏作用。研究表明，除了其渗透作用外，甘油还具有保护功能，并能稳定杜氏盐藻细胞中的PS2 PPC。
