FORMATION AND PROPERTIES OF C1-INHIBITOR POLYMERS

Heating of the serpin C1-inhibitor above 55 degrees C induced the form ation of inactive polymers. Western blotting of non-denaturing gels sh owed that the polymers bound to the conformation specific monoclonal a ntibody 4C3, suggesting that a similar conformational change to that o ccurring in complexed or cleaved inhibitor had taken place. N-Terminal analysis of tryptic peptides which bound to 4C3 showed that the epito pe resides within residues 288-444, a region which includes parts of b eta-sheets A and C. alpha(1)-Antichymotrypsin, a(2)-antiplasmin, angio tensinogen and thyroxine binding globulin also polymerised on heating, indicating that this is a property of many serpins.