水稻幼苗根细胞质膜和液泡膜微囊Ca^(2+)-ATP酶的特性  

Characteristics of Ca^(2+)-ATPase of Plasma Membrane and Tonoplast Membrane Vesicles from Roots of Rice Seedlings

作　　者：王精明[1] 李洪清[2] 李美茹[3] 

机构地区：[1]惠州学院理学系,惠州516015 [2]华南师范大学生命科学学院,广州510631 [3]中国科学院华南植物研究所,广州510650

出　　处：《植物生理学通讯》2004年第1期22-26,共5页Plant Physiology Communications

基　　金：国家自然科学基金项目(30170667)

摘　　要：水稻幼苗根质膜和液泡膜Ca2+-ATP酶对ATP的Km值分别为7.1和4.5μmol.L-1;反应的最适pH分别为8.0和7.0。两者活性均受Na3VO4和曙红B(EB)抑制;CPZ抑制质膜Ca2+-ATP酶活性,但促进液泡膜Ca2+-ATP酶活性。30mmol.L-1CaCl2浸种和CaCl2浸种结合低温锻炼预处理,均可提高此酶的活性和冷稳定性。Plasma and tonoplast membrane-enriched vesicles were prepared from rice seedling root by DextranT70 gradient centrifugation. Ca2+-ATPase of both vesicles were identified. The Km values for ATP of Ca2+-ATPase of plasma membrane and tonoplast membrane vesicles are 7.1 and 4.5 μmol.L-1 respectively, and theoptimum pH values of the two vesicles were 8.0 and 7.0, respectively. The enzyme activities of both vesicleswere inhibited by Na3VO4 and erythrosin B (EB).The activity from plasma membrane was inhibited by chlor-promazine (CPZ), but the activity from tonoplast membrane was promoted by CPZ. However, the enzymeacitivties and its cold stability of both vesicles were improved by rice seed-submerged in CaCl2 treatment orseedling-cold-hardened treatment following seed-submerged in CaCl2 treatment.

关 键 词：水稻幼苗 根细胞 质膜 液泡膜 CA^2+-ATP酶 

分 类 号：S511[农业科学—作物学] Q945[生物学—植物学]