Acclimatory responses to high-salt stress in Chlamydomonas (Chlorophyta, Chlorophyceae) from Antarctica  

作　　者：KAN Guangfeng SHI Cuijuan WANG Xiaofei XIE Qiuju WANG Min WANG Xinlei MIAO Jinlai 

机构地区：[1]School of Marine Science and Technology,Harbin Institute of Technology at Weihai,Weihai 264209,China [2]Key Laboratory of Marine Bio-active Substances,State Oceanic Administration,Qingdao 266061,China

出　　处：《Acta Oceanologica Sinica》2012年第1期116-124,共9页海洋学报（英文版）

基　　金：The National Natural Science Foundation of China under contract No.31100090;Shandong Provincial Natural Science Foundation of China under contract No.ZR2010DQ010;the Fundamental Research Funds for the Central Universities under contract No.HIT.IBRSEM.2009148

摘　　要：Antarctic ice microalga can survive and thrive in channels or pores containing high salinity in Antarctic ice layer. In this study, it was found that cell membrane permeability of green microalga Chlaraydomonas sp. L4 from Antarctic sea ice was high in cells treated with hypersalinity due to the induction of active oxygen and radicals. However, increased super oxide dismutase （SOD） scavenged harmful free radicals effectively to keep cell membrane integrity. Also, the analysis of membrane fatty acids demonstrated the content of saturated fatty acids and monounsaturated fatty acids in- creased and polyunsaturated fatty acids decreased under the high-salt treatment for 14 d, which effectively reduced the membrane fluidity and minimized the injury to cell membrane. The morpho- logical changes showed that hypersalinity induced the increase of cell volume and the consumption of starch granules. However, because of the increase in detoxification of vacuoles, electron-dense deposits and SOD activity under high-salt stress, the complete noninterference thylakoids, mito- chondria and cell nucleus maintained cellular fundamental metabolism. Global-expression profiling of proteins showed eight protein spots disappeared, 18 protein spots decreased and 18 protein spots were enhanced after the high-salt shock obviously （P 〈0.05）. One new peptide （pI 6.90; MW 51 kDa） was primarily confirmed as the processor of light reaction center protein CP43 in photosystem II, which increased photosynthesis ability of Chlamydomonas sp. L4 treated with high salinity.Antarctic ice microalga can survive and thrive in channels or pores containing high salinity in Antarctic ice layer. In this study, it was found that cell membrane permeability of green microalga Chlaraydomonas sp. L4 from Antarctic sea ice was high in cells treated with hypersalinity due to the induction of active oxygen and radicals. However, increased super oxide dismutase （SOD） scavenged harmful free radicals effectively to keep cell membrane integrity. Also, the analysis of membrane fatty acids demonstrated the content of saturated fatty acids and monounsaturated fatty acids in- creased and polyunsaturated fatty acids decreased under the high-salt treatment for 14 d, which effectively reduced the membrane fluidity and minimized the injury to cell membrane. The morpho- logical changes showed that hypersalinity induced the increase of cell volume and the consumption of starch granules. However, because of the increase in detoxification of vacuoles, electron-dense deposits and SOD activity under high-salt stress, the complete noninterference thylakoids, mito- chondria and cell nucleus maintained cellular fundamental metabolism. Global-expression profiling of proteins showed eight protein spots disappeared, 18 protein spots decreased and 18 protein spots were enhanced after the high-salt shock obviously （P 〈0.05）. One new peptide （pI 6.90; MW 51 kDa） was primarily confirmed as the processor of light reaction center protein CP43 in photosystem II, which increased photosynthesis ability of Chlamydomonas sp. L4 treated with high salinity.

关 键 词：Antarctic ice microalga SOD enzymes ultra structure membrane fatty acids difference protein hypersaline acclimation 

分 类 号：Q949.21[生物学—植物学] TQ028.8[化学工程]