Banerjee C, Sarkar D
Leishmania Division, Indian Institute of Chemical Biology, Calcutta.
Mol Biochem Parasitol. 1992 Jun;52(2):195-205. doi: 10.1016/0166-6851(92)90052-l.
We describe here a protein kinase from the promastigote form of the parasitic protozoan, Leishmania donovani, purified to near homogeneity to a single-subunit, 34-kDa protein. This enzyme does not require a cofactor, and has several characteristics in common with the catalytic subunit of mammalian cAMP-dependent protein kinase, for example, preference for kemptide as a substrate, phosphorylation of serine residues of protamine and inhibition by the mammalian heat-stable inhibitor. The leishmanial enzyme can associate with the regulatory subunit of mammalian cAMP-dependent protein kinase to form an inactive holoenzyme that is activated by cAMP and is protected from inhibition by thiol reagents. From these results it is concluded that L. donovani promastigotes possess a protein kinase which has similar characteristics with the mammalian catalytic subunit of cAMP-dependent protein kinase.
我们在此描述了一种来自寄生原生动物杜氏利什曼原虫前鞭毛体形式的蛋白激酶，该酶被纯化至接近同质，为一种单亚基、34 kDa的蛋白质。这种酶不需要辅因子，并且具有与哺乳动物cAMP依赖性蛋白激酶催化亚基的几个共同特征，例如，优先选择kemptide作为底物、对鱼精蛋白丝氨酸残基进行磷酸化以及被哺乳动物热稳定抑制剂抑制。利什曼原虫的这种酶可以与哺乳动物cAMP依赖性蛋白激酶的调节亚基结合形成无活性的全酶，该全酶被cAMP激活并受到硫醇试剂抑制的保护。从这些结果可以得出结论，杜氏利什曼原虫前鞭毛体拥有一种与哺乳动物cAMP依赖性蛋白激酶催化亚基具有相似特征的蛋白激酶。
