Buron I, Garcia Herdugo G, Navas P
Comp Biochem Physiol B. 1987;86(2):241-4. doi: 10.1016/0305-0491(87)90284-7.
The specific activity of K+-dependent p-NPPase (paranitrophenylphosphatase) from frog (Rana ridibunda) epidermis microsomal preparation was determined. The activity was proportional to time of incubation and protein concentrations under our assays conditions. Optimal phosphatase activity was at pH from 8 to 9 and over 35 degrees C. 10(-3) M ouabain inhibited 100% of the activity and the Ki was estimated about 5 X 10(-5) M. The Km for p-NPP was 3.8 mM and 2.1 for K+. The lectins GSI and GSII produced 80-90% of non-competitive inhibition of the activity. 50% of inhibition by GSI was obtained at 2 micrograms/ml. The Km for p-NPP did not change but the Vmax of activity was clearly reduced for both GSI and GSII lectins.
测定了来自青蛙（食用蛙）表皮微粒体制剂的钾依赖性对硝基苯磷酸酶（p-NPPase）的比活性。在我们的测定条件下，该活性与孵育时间和蛋白质浓度成正比。最佳磷酸酶活性在pH值为8至9且温度超过35摄氏度时出现。10⁻³M哇巴因抑制了100%的活性，其抑制常数（Ki）估计约为5×10⁻⁵M。对硝基苯磷酸（p-NPP）的米氏常数（Km）为3.8mM，钾离子的Km为2.1。凝集素GSI和GSII对该活性产生80 - 90%的非竞争性抑制。GSI在2微克/毫升时产生50%的抑制作用。对于GSI和GSII凝集素，p-NPP的Km没有变化，但活性的最大反应速度（Vmax）明显降低。
