高级检索+

猕猴桃果实细胞中超氧化物歧化酶的纯化及性质研究

PURIFICATION AND SOME PROPERTIES OF COPPER/ZINC SUPEROXIDE DISMUTASE IN ACTINIDIA CHINENSIS FRUITS

  • 摘要: 本文采用硫酸铵盐析、Sephadex G-100、DEAE-纤维索层析,首次从猕猴桃果实细胞中提纯了超氧化物歧化酶。并从不同角度鉴定了酶制备物的纯度,认为它达到均一程度,酶比活力为每毫克蛋白质1340单位;SDS聚丙烯酰胺凝胶电泳为一条带,氨基酸末端为丙氨酸;酶亚基含氨基酸16种,大约由157种氨基酸残基组成;紫外可见光区最大吸收峰分别为270nm和676nm,同时,用金属Co和Zn对CuZn—SOD中金属离子进行了取代研究。

     

    Abstract: In this paper, it is first reported that Copper/Zinc Superoxide dismutase from Actinidia fruits has been isolated and purified and some properties have been studied. Purification by ammonium sulfate fractionation remove pectin, Sephadex G-100 gel filtration and DEAE-cellulose chromatorgraphy, 0.56mg CuZn-SOD with specific activity 1340 units per mg protein was obtained from 242g Actinidia fruits. The purified enzyme is found to be homogenous by the analysis of PAGE, SDS-PAGE, N-terminal aminoacid.SOD in the Actinidia fruits exhibits a absorption maximum in the ultravioiet at 270nm, and another in visible at 676nm. the enzyme Subunit molecular weight and molecular weight are 16800 and 33800 d. t. respectively. The subunit consists of approximate 157 amino acid residues, in which tryptophan residue is absent. The N-terminal amino acid is Ala as assayed by dansyl chloride, and replacement studies of the metal ions in the enzyme have been carried out using the metal Co and Zn.

     

/

返回文章
返回