花生幼苗下胚轴质膜Ca^(2+)-ATP酶及其对低温胁迫的反应  

PLASMALEMMA ATPase OF HYPOCOTYL OF PEANUT SEEDLING AND ITS REACTION TO LOW TEMPERATUER STRESS

作　　者：李美茹[1] 杜延茹[2] 郭立波 

机构地区：[1]中国科学院华南植物研究所,广州510650 [2]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2期110-114,共5页Journal of Wuhan Botanical Research

基　　金：蔡火石生物科学发展基金

摘　　要：经６％ ～１２％ Ｄｅｘｔｒａｎ Ｔ７０ 密度梯度离心，获得了纯度较高的７ ｄ 龄花生幼苗下胚轴质膜制剂。质膜Ｃａ２＋ －ＡＴＰａｓｅ在反应系统不存在Ｍｇ２＋ 时，可正常表现水解ＡＴＰ的活性，但此活性明显低于Ｍｇ２＋ 激活的ＡＴＰａｓｅ。Ｃａ２＋ －ＡＴＰａｓｅ不受Ｎａ３ＶＯ４ 抑制，不被Ｋ＋ 激活，而被Ｃｌ－ 抑制。Ｃａ２＋ －ＡＴＰａｓｅ的最适ｐＨ不同于Ｍｇ２＋ 激活的ＡＴＰａｓｅ。低温胁迫显著提高质膜Ｃａ２＋ －ＡＴＰａｓｅ的活性，推测Ｃａ２＋ －ＡＴＰａｓｅ参与胞质中Ｃａ２＋ 浓度变化的调节。Plasma membrane were obtained from 7 day old peanut seedling hypocotyl by 6%～12% Dextran T70 density gradient centrifugation,with high quality and purity.Plasmalemma ATPase acts normally as hydrolyzing ATP without Mg 2+ in reaction system, but the activity was lower than Mg 2+ activated ATPase.Ca 2+ ATPase wasn′t inhibited by Na 3VO 4 and wasn′t activitied by K +,whereas it is inhibited by Cl -.The optimum pH of Ca 2+ ATPase is different from that of Mg 2+ activated ATPase.Plasma membrane Ca 2+ ATPase activity increased notably under low temperature stress.It is suggest that the possible role of Ca 2+ ATPase is adjusting Ca 2+ concentration on cytoplasms.

关 键 词：花生幼苗下胚轴 质膜Ca^2+-ATPase 低温胁迫 

分 类 号：S565.201[农业科学—作物学]