The interaction between plasminogen and antiplasmin variants as studied by surface plasmon resonance.
The interaction between immobilized plasminogen or an elastase-degradation product from plasminogen, constituting "kringles" 1-3 and different purified variants of antiplasmin has been studied by surface plasmon resonance utilising a BIAcore. The antiplasmin variants studied are wild-type, K429E, K436E, E443G, D444G, K452E and K452T. It is shown that the two mutants K452T and K452E react in quite a similar way as wt-antiplasmin, suggesting that Lys452 is not involved in the lysine-binding site interaction between plasminogen and antiplasmin. On the other hand, the mutant K436E displays a much lower k(a). The affinity between plasminogen or the fragment constituting "kringles" 1-3 and K436E were also much lower than with wt-antiplasmin. Thus, also the data obtained with surface plasmon resonance show that Lys436 indeed is very important in the lysine-binding site mediated interaction between plasminogen and antiplasmin.
Wang
Haiyao
H
Department of Clinical Chemistry and Blood Coagulation, Karolinska University Hospital, Karolinska Institutet, Stockholm, Sweden.
Karlsson
Anna
A
Sjöström
Iréne
I
Wiman
Björn
B
D004591:Electrophoresis, Polyacrylamide Gel; D016297:Mutagenesis, Site-Directed; D010958:Plasminogen / Q000378:metabolism*; D011485:Protein Binding; D020349:Surface Plasmon Resonance; D000979:alpha-2-Antiplasmin / Q000235:genetics / Q000378:metabolism*
D000979:alpha-2-Antiplasmin; D010958:Plasminogen