盐生杜氏藻质膜ATPase及其对高渗震动的反应  

PLASMALEMMA ATPase OF DUNALIELLA SALINA AND ITS RELATION TO HYPEROSMOTIC SHOCK

作　　者：杜延茹[1] 贾媛[1] 李洪泉[1] 

机构地区：[1]哈尔滨师范大学生物系,哈尔滨150080

出　　处：《武汉植物学研究》1999年第1期10-14,共5页Journal of Wuhan Botanical Research

基　　金：蔡火石生物科学发展基金

摘　　要：用水溶性多聚物 ( dextran T5 0 0 PEG 335 0 )两相法制备盐生杜氏藻细胞质膜 ,经检测质膜纯度较高 ,原位膜约占 78%。质膜 ATPase的动力学常数 Km 和 Vmax分别为0 5 8mmol L和 4 3 5 9μmol Pi ( mg protein· h) ;最适 p H值是 7 5。质膜 ATPase的活性随Mg Cl2 和 Ca Cl2 浓度的升高而增加 ,但较高浓度的 Mg Cl2 和 Ca Cl2 有轻微的抑制作用 ;KCl促进质膜 ATPase的活性 ,在 1 0 0 mmol L时达到最大 ,高于 1 0 0 mmol L时抑制效应显著。钒酸钠、DES、DCCD和 NEM明显地抑制质膜 ATPase的活性 ;而 Na N3、Na NO3、Na Mo O4和KCN对质膜 ATPase的活性影响不大。高渗震动刺激了质膜 ATPase的活性。A fraction enriched in plasma membrane from Dunaliella salina was obtained by apueous two phase partition system (dextran T500/polyethylene glycol 3350),with high quality and purity.The K m of plasmalemma ATPase was found to be 0.58 mmol/L,its V max was 43.59 μmol Pi/(mg protein·h) and the optimum pH 7.5.Enzyme activity was stimulated by the increase of concentration of MgCl 2,CaCl 2 and KCl,but much higher concentrations had a little inhibitory effect.The plasmalemma ATPase exhibited great sensitivities to vanadate,dicyeclohexyl carbodiimide (DCCD),SH regent N ethylmaleimide (NEM),especially to diethylstibestro (DES),whereas it was insensitive to azide,nitrate,molybdate and cyanide.The ATPase activity was notably increased following hyperosmotic shock,and its possible role in osmoregulation was discussed.

关 键 词：盐生杜氏藻 质膜ATPase 高渗震动 

分 类 号：Q949.211[生物学—植物学]