Mechanism of thrombin inhibition by heparin cofactor II and antithrombin in the presence of the ray (Raja radula) skin dermatan sulfate

DS from ray skin catalyzes the thrombin inhibition by HCII or AT primarily by forming a DS-inhibitor complex more reactive than the free inhibitor towards the protease. The affinity of DS for HCII was approximately 2-fold higher whereas the catalyzed reaction rate constant was approximately 20-fold higher when compared to AT.