title: Some molecular and functional changes in high molecular weight kininogen induced by plasmin and trypsin.
abstract: When purified human HMW-kininogen was digested by plasmin, its specific antigenic properties were initially enhanced and then gradually destroyed, but its clot-promoting activity (Fitzgerald factor activity) was only slightly decreased. When endogenous serum plasminogen was activated by streptokinase, similar alterations in specific HMW-kininogen antigens and Fitzgerald factor activity occurred. In contrast, trypsin induced increased antigenic properties initially, but readily destroyed the Fitzgerald factor activity and less readily destroyed the specific HMW-kininogen antigenic properties in purified HMW-kininogen and in normal human serum. When normal serum was treated with streptokinase, the antigenic properties shared by HMW and LMW-kininogens were in Sephadex G-200 fractions of lower molecular weight than in the case of untreated serum, but the elution volumes of specific HMW-kininogen antigens and Fitzgerald factor activity were not significantly altered. When prekallikrein-deficient serum was subjected to the same G-200 gel filtration process, there was a broad overlap in the elution volumes of antigens shared by both HMW and LMW-kininogens with specific HMW-kininogen antigenic and coagulant properties, which remained after streptokinase treatment of the serum. Depsite the disparate rates of destruction of the antigenic and clot-promoting portion of HMW-kininogen by proteases these properties did not separate from one another during ion exchange chromatography.
mesh_terms: D001779:Blood Coagulation Factors / Q000502:physiology; D002850:Chromatography, Gel; D004591:Electrophoresis, Polyacrylamide Gel; D000939:Epitopes; D005341:Fibrinolysin / Q000494:pharmacology*; D006801:Humans; D007704:Kininogens / Q000276:immunology / Q000502:physiology; D008970:Molecular Weight; D011288:Prekallikrein / Q000502:physiology; D011487:Protein Conformation; D013300:Streptokinase / Q000494:pharmacology; D014357:Trypsin / Q000494:pharmacology*
chemical_list: D001779:Blood Coagulation Factors; D000939:Epitopes; D007704:Kininogens; D011288:Prekallikrein; D013300:Streptokinase; D014357:Trypsin; D005341:Fibrinolysin