Hasunuma K, Miyamoto-Shinohara Y, Furukawa K
Biochem Biophys Res Commun. 1987 Aug 14;146(3):1178-83. doi: 10.1016/0006-291x(87)90772-8.
Six fractions of GTP-binding proteins separated by gel filtration of a mycelial extract containing membrane components of Neurospora crassa were partially characterized. [35S]GTP gamma S bound to GTP-binding protein was assayed by repeated treatments with a Norit solution and centrifugation. The binding of [35S]GTP gamma S to GTP-binding proteins was competitively prevented in the presence of 0.1 to 1 mM GTP but not in the presence of ATP. These GTP-binding proteins fractionated by the gel column had Km values of 20, 7, 4, 4, 80 and 2 nM. All six fractions of these GTP-binding proteins showed the capacity to be ADP-ribosylated by pertussis toxin.
通过对含有粗糙脉孢菌膜成分的菌丝体提取物进行凝胶过滤，分离出了六部分GTP结合蛋白，并对其进行了部分特性鉴定。通过用Norit溶液反复处理并离心来测定与GTP结合蛋白结合的[35S]GTPγS。在0.1到1 mM GTP存在时，[35S]GTPγS与GTP结合蛋白的结合受到竞争性抑制，但在ATP存在时则不受影响。经凝胶柱分级分离的这些GTP结合蛋白的Km值分别为20、7、4、4、80和2 nM。这些GTP结合蛋白的所有六个部分都显示出被百日咳毒素ADP核糖基化的能力。
