Summary
It was found that the activation of the FSF by thrombin in the presence of calcium
ions takes place with a transitory increase of additional SH groups in the FSF.
The activation of the FSF and the loss of its activity in the conversion of fibrin
polymer to desmofibrin occurs simultaneously with the increase and decrease of additional
SH groups.
It is considered that in the transition of fibrin polymer to desmofibrin, the disulphide
bonds exchange mechanism is involved, if not as a final reaction, at least as a phase
in that mechanism.