摘要
经硫酸铵分部沉淀,DEAE-纤维素(DE 52),Sepharose 6B和 AH—4B连续三次柱层析,得到纯化88倍电泳均一的菠菜叶片蔗糖磷酸合成酶。电泳分析该酶分子量为490 kD,是由八个分子量为60 kD的相同亚基组成的寡聚体,等电点为PI=4.l,其最适pH值为6.9。
Sucrose phosphate synthetase (EG 2.4.1.14)from spinach leaves has been purified to 88 fold(Table 1) by ammonium sulfate fractiona-tion and column chromatography of DEAE-cellulose, Sepharose 6B and AH-Sepharose-4B(Fig. 2). The enzyme preparation obtained wasshown to be homogeneous as examined by gra-dient polyacrylamide gel electrophoresis (Fig. 3).The enzyme have an approximately molecularweight 490 kD (Fig. 4). SDS-polyacrylamidegel electrophoresis shown that this enzymeconsists of eight identical subunits, each havea molecular weight 60 kD (Fig. 5, 6). Thepurified enzyme had a pH optimum atpH 6. 9 (Fig. 8) and the isoelectric point at4. 1 (Fig. 7).
关键词
菠菜叶片
磷酸合成酶
蔗糖
纯化
spinack leaf
sucrose phosphate synthetase
purification
