Fig. 6. Binding studies in solution. (A) Formation of the ternary complex haemadin–thrombin–triabin, as followed using non-denaturant PAGE. Lane 1, human α-thrombin (5 µg); lane 2, haemadin (10 µg); lane 3, triabin (20 µg); lane 4, thrombin–haemadin complex (10 µg); lanes 5–7, 10 µg of thrombin–haemadin complex incubated with increasing amounts of triabin (1:1, 1:1.5 and 1:2 equivalents); lane 9, human α-thrombin–triabin complex (10 µg). (B) Haemadin binds to thrombomodulin-bound thrombin, but not to meizothrombin. Lane 1, 10 µg of human thrombin–TME456; lane 2: 10 µg of the complex incubated with 1 µg haemadin; lane 3, 10 µg of meizothrombin; lane 4, 10 µg meizothrombin incubated with 1.5 µg haemadin; lane 5, 20 µg triabin; lane 6, human thrombin–triabin complex (10 µg).