Ca++ binding properties of human prothrombin.
The binding of Ca++ to human prothrombin has been investigated by equilibrium dialysis. The protein exhibited a positive cooperativity phenomenon for the first three Ca++ bound. Eleven to twelve Ca++ binding sites have been found. They could be differentiated in terms of two classes of sites with respect to their Ca++ affinity: 5 strong binding sites (log Kassoc = 3.9) and 7 weak binding sites (log Kassoc = 2.9). We attempted to determine the Hill coefficient of the strong binding sites responsible for cooperativity. Results have been compared to data previously reported for bovine prothrombin.
D000818:Animals; D001665:Binding Sites; D002118:Calcium; D002417:Cattle; D006801:Humans; D006863:Hydrogen-Ion Concentration; D011485:Protein Binding; D011516:Prothrombin
D011516:Prothrombin; D002118:Calcium