Inactivation of Factor C by dimethyl sulfoxide inhibits coagulation of the Carcinoscorpius Amoebocyte Lysate

Abstract

The inhibition by dimethyl sulfoxide of the coagulation of the Carcinoscorpius Amoebocyte Lysate was found to be due to the inactivation of Factor c enzyme in the coagulation cascade and not due to the inactivation of proclotting enzyme as earlier reported in studies done on Limulus. Kinetic studies on both purified enzymes revealed that dimethyl sulfoxide completely but reversibly inhibited the activation of Factor C by endotoxins in a non-competitive manner whereas, it did not inhibit, albeit retard the activity of proclotting enzyme. This result also explains why clotting enzyme was shown to be largely unaffected by dimethyl sulfoxide.