On the plasminogen-activating function of streptokinase.
1. Several hypotheses have been advanced to explain the activating function of streptokinase. The predominant hypothesis suggests a stable equimolar streptokinase-plasmin(ogen) complex, activating free plasminogen by an active centre, which is located in the plasmin(ogen) part of the complex. 2. This hypothesis cannot explain a number of phenomena and certain accumulated experimental data, for example: rabbit and bovine plasminogen activation by streptokinase, not forming stable complexes with these plasminogens; possible activation with pH less than or equal to 2, in the presence of urea, during modification of streptokinase tyrosine residues, i.e. when these two proteins cannot form a stable complex. 3. On the basis of acquired experimental data the following concept is suggested: the activating function of streptokinase is oxygen-dependent and is realised with the help of superoxide radical due to the O(2-.)-generating ability of plasminogen and the O(2-.)-converting ability of streptokinase.
Nikandrov
V N
VN
Laboratory of Biochemistry, Byelorussian Research Institute of Epidemiology and Microbiology, Minsk, U.S.S.R.
D000818:Animals; D006801:Humans; D010960:Plasminogen Activators; D013300:Streptokinase / Q000378:metabolism*
D013300:Streptokinase; D010960:Plasminogen Activators