Chandra S, Adhikary G, Sikdar R, Sen P C
Department of Chemistry, Bose Institute, Calcutta, India.
Biochim Biophys Acta. 1993 Aug 16;1144(1):33-8. doi: 10.1016/0005-2728(93)90027-d.
A protein isolated from rat brain cytosol is found to inhibit Na+/K(+)-ATPase in rat brain and kidney and H+/K(+)-ATPase from toad gastric mucosa, but has no effect on Ca2+,Mg(2+)-ATPase and Ca(2+)-ATPase isolated either from rat testis or goat spermatozoa. The inhibitor has been partially purified by ammonium sulphate precipitation followed by gel-filtration through Sephadex G-100. The inhibitor seems to bind at or close to the ATP binding site of Na+/K(+)-ATPase, such that the binding of the inhibitor to ATPase is reversible and competitive in nature with respect to the substrate. Optimum inhibition is observed at around the phase transition temperature of brain Na+/K(+)-ATPase and the inhibitory activity is only partially dependent on -SH or -NH2 group(s) of the inhibitor protein.
从大鼠脑细胞质中分离出的一种蛋白质被发现可抑制大鼠脑和肾中的钠钾ATP酶以及蟾蜍胃黏膜中的氢钾ATP酶，但对从大鼠睾丸或山羊精子中分离出的钙镁ATP酶和钙ATP酶没有影响。该抑制剂已通过硫酸铵沉淀，随后经葡聚糖凝胶G - 100凝胶过滤进行了部分纯化。该抑制剂似乎在钠钾ATP酶的ATP结合位点处或附近结合，使得抑制剂与ATP酶的结合在性质上是可逆的，并且相对于底物具有竞争性。在脑钠钾ATP酶的相变温度左右观察到最佳抑制效果，并且抑制活性仅部分依赖于抑制剂蛋白的巯基或氨基基团。
