摘要
经提纯的人脑癌细胞质膜蛋白激酶在Mg^(2+)和Mn(2+)存在下,有很高的酶活性。多种去垢剂及NaF处理能提高酶活性,SDS和pCMPS(p-chloromercu-riphenyl Sulfonate)是该酶的抑制剂。以γ-^(32)P-ATP作底物时该酶的Km为0.67μmol。各种核苷酸及其衍生物能影响酶活测定。蛋白激酶能磷酸化内源和外源蛋白中的组蛋白和酪蛋白。1%TritonX-100能增溶入脑癌细胞质膜。
Purified plasma membranes from human astrocytoma exhibit very high proteinkinase activity. This activity is dependent on Mg^(2+) or Mn^(2+), and is stronglyactivated by detergents and NaF. Under optimal conditions (with detergent andvanadate)its specific activity is 0.2, 0.3 nmol/(min·mg^(-1)). The membrane proteinkinase showed a low Km for ATP (6.7μmol/L). It was inhibited by SDS andp-chloromercuriphenyl sulfonate. Also inhibited by nucleotide derivatives. Thekinase could phosphorylates both endogeneous and exogeneous substrates, e.g.histone and casein. It was solubilized by using Triton X-100 (1%) in the presenceof sucrose at pH 7.4.
出处
《复旦学报（自然科学版）》
CAS
CSCD
北大核心
1989年第3期331-337,共7页
Journal of Fudan University：Natural Science
关键词
人
脑
细胞质膜
蛋白
激酶
增溶
human
brain
carcinoma
plasma membranes
protein
kinase
properties
solubilization.
