Effects of alpha 2-plasmin inhibitor on plasminogen activation by staphylokinase/plasminogen complex.
Using a stable cross-linked SAK/plg complex, the effects of alpha 2-plasmin inhibitor on plasminogen activation by SAK were investigated. alpha 2-Plasmin inhibitor inhibited dose-dependently plasminogen activation by the SAK/plg complex. When FCB-2 or EACA was added to the reaction mixture of SAK/plg complex and alpha 2-plasmin inhibitor, the inhibitory activity of alpha 2-plasmin inhibitor was abolished and the enzymatic activity of the complexes was restored. alpha 2-Plasmin inhibitor inhibited the activity of the SK/plg complex, but neither FCB-2 nor EACA restored the plasminogen activator activity in the mixture of SK/plg complex and alpha 2-plasmin inhibitor. Using 125I-labeled SAK/plg complex or SK/plg complex, the reaction of the complex with alpha 2-plasmin inhibitor was analyzed. The SAK/plg complex produced a new complex with alpha 2-plasmin inhibitor. The formation of a new high molecular weight complex with alpha 2-plasmin inhibitor was abolished by both EACA or FCB-2. With regard to the SK/plg complex, neither EACA nor FCB-2 suppressed the complex formation with alpha 2-plasmin inhibitor. These findings indicate that the SAK/plg complex binds to fibrin, and that this complex expresses plasminogen activator activity without being affected by alpha 2-plasmin inhibitor.
Okada
K
K
Department of Physiology, Kinki University School of Medicine, Osakasayama, Japan.
Nonaka
T
T
Matsumoto
H
H
Fukao
H
H
Ueshima
S
S
Matsuo
O
O
D000595:Amino Acid Sequence; D015119:Aminocaproic Acid / Q000494:pharmacology; D008666:Metalloendopeptidases / Q000378:metabolism; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000494:pharmacology; D010958:Plasminogen / Q000037:antagonists & inhibitors* / Q000378:metabolism; D011485:Protein Binding; D000979:alpha-2-Antiplasmin / Q000494:pharmacology*
D010446:Peptide Fragments; D000979:alpha-2-Antiplasmin; D010958:Plasminogen; D008666:Metalloendopeptidases; C022653:auR protein, Staphylococcus aureus; D015119:Aminocaproic Acid