肽洗涤剂PD1影响大鼠脑皮质膜的GTP酶活性。

Peptitergent PD1 affects the GTPase activity of rat brain cortical membranes.

作者信息

Bavec A, Juréus A, Cigić B, Langel U, Zorko M

机构信息

Institute of Biochemistry, Medical Faculty, University of Ljubljana, Slovenia.

出版信息

Peptides. 1999;20(2):177-84. doi: 10.1016/s0196-9781(98)00162-4.

DOI:10.1016/s0196-9781(98)00162-4

PMID:10422872

Abstract

Peptitergent PD1 shows complex effects on GTPase activity of rat brain cortical membranes: inhibition in the presence of lower concentrations of GTP and activation at a higher concentration, above 0.5 microM, of GTP. Its effect is dose dependent and is characterized by an EC50 of 1.8 +/- 0.2 microM and a Hill coefficient of 1.6 +/- 0.3, and it increases both Km and Vmax of the GTP hydrolysis. PD1 that was unable to solubilize G-proteins from the membranes probably acts on them by direct binding near the C-terminal alpha-helical region of the Galpha subunit, similarly to mastoparan.

摘要

肽洗涤剂PD1对大鼠脑皮质膜的GTP酶活性表现出复杂的影响：在较低浓度的GTP存在下具有抑制作用，而在较高浓度（高于0.5微摩尔/升）的GTP时则具有激活作用。其作用呈剂量依赖性，EC50为1.8±0.2微摩尔/升，希尔系数为1.6±0.3，并且它增加了GTP水解的Km和Vmax。无法从膜中溶解G蛋白的PD1可能通过与Gα亚基C末端α-螺旋区域附近直接结合而作用于它们，类似于蜂毒素。