水稻液泡膜H^＋—ATPase的分离纯化及生化性质研究

ISOLATION,PURIFICATION AND CHARACTERIZATION OF THE TONOPLAST H￣+-ATPase FROM ETIOLATED SEEDLING OF RICE

用差速离心和密度梯度离心的方法，分离水稻液泡膜微囊，测定膜微囊ＡＴＰａｓｅ活性．用５％的ＴｒｉｔｏｎＸ－１００溶膜后的上清液，经ＳｅｐｈａｒｏｓｅＣＬ－６Ｂ柱层析纯化，得到ＡＴＰａｓｅ复合物．生化性质研究结果表明，纯化前后基本相似．酶活性需要Ｍｇ２＋，受Ｃｌ－激活，对叠氮化钠、钒酸盐和寡霉素不敏感，受硝酸盐、ＤＣＣＤ（质子通道抑制剂）抑制，泵质子产生的膜电位△可被质子通道的离子载体ＣＣＣＰ破坏．

The tonoplast vesicles were obtained from etiolated seedling of rice by the discontinuous sucrose gradient centrifugation. The results indicated that Mg2+ was necessary for the tonoplast H+-ATPase activity of rice,that was stimulated by Cl- and inhibited by NO, DCCD,but it was insensitive to NaN3,Na3VO4 (NH4)MoO4 and oligomycin,The membrane potential ()induced by tonoplast H+-ATPase of rice was collapsed by CCCP. Solubilizing tonoplast vesicles with Triton X-100 and purifying ATPase complex with Sepharose CL-6B chromatography,the partial pure enzyme was obtained. The purified ATPase has the similar properties to that of native enzyme.