The serine protease plasmin can efficiently degrade amyloid peptide in vitro, and is found at low levels in the hippocampus of patients with Alzheimer's disease (AD). The cause of such paucity remains unknown. We show here that the levels of total brain plasminogen and plasminogen-binding molecules are normal in these brain samples, yet plasminogen membrane binding is greatly reduced. Biochemic...

The rate of diffusion of a protein in solution from a source in agar gel is, within limits, proportional to its original concentration (Ouchterlony, 1949). When plasminogen in biological fluids is allowed to diffuse from a source in agar/fibrinogen gel for a given time, the distance diffused can be ascertained by activation of the plasminogen to plasmin by streptokinase after diffusion has take...

α-Enolase is a glycolytic enzyme and a surface receptor for plasminogen. α-Enolase-bound plasminogen promotes tumor cell invasion and cancer metastasis by activating plasmin and consequently degrading the extracellular matrix degradation. Therefore, α-enolase and plasminogen are novel targets for cancer therapy. We found that the amino acid sequence of a peptide purified from enzymatic hydrolys...

As reported in the previous paper by the authors, two kinds of precursor of plasminogen activator were presented by gel filtration method, which were named proactivator A and proactivator B.1) However the former fraction did not contain plasminogen, the latter on the other hand always coexisted with plasminogen, which seemed to be difficult to separate. Therefore, a question arises that fibrino...

Mice lacking the serine protease tissue plasminogen activator (tPA) are resistant to excitotoxin-mediated hippocampal neuronal degeneration. We have used genetic and cellular analyses to study the role of tPA in neuronal cell death. Mice deficient for the zymogen plasminogen, a known substrate for tPA, are also resistant to excitotoxins, implicating an extracellular proteolytic cascade in degen...

Plasminogen is a key proenzyme in the fibrinolytic and thrombolytic systems. Congenital deficiency of plasminogen and molecular abnormality of plasminogen (dysplasminogenemia) have been reported in association with the thrombotic tendency in human. In dysplasminogenemia, the level of immunoreactive plasminogen is normal, although the functional activity is reduced. Human plasminogen gene spans ...

In this study, the role of the staphylococcal plasminogen activator, staphylokinase (SAK), was analyzed for its ability to mediate acquisition of cell-associated plasmin-like activity by staphylococci in the presence of a source of human plasminogen. A panel of staphylococcal strains isolated from humans was tested for the presence of the SAK gene, secretion of the plasminogen activator, and th...

Plasminogen isolated from 60 full-term newborns differs from adult plasminogen in carbohydrate composition, kinetic activation constants, and cell binding. Amino acid composition and amino-terminal sequence analysis data indicate that the plasminogens of neonates and adults have the same amino acid sequence. Like the adult, the neonate has two glycoforms, but both have significantly more mannos...

Highly purified pro-urokinase (pro-UK) or single-chain urokinase-type plasminogen activator (scu-PA) was treated with diisopropylfluorophosphate (1 mmol/L) to eliminate traces of two-chain UK activity. This preparation was found to retain a low activity against a chromogenic substrate (S2444), equivalent to 0.1% to 0.5% of the activity of its plasmin-activated derivative. Evidence is presented ...

Tissue plasminogen activator (t-PA) and/or pro-urokinase (pro-UK) induced lysis of standard 125I-fibrin clots suspended in plasma was studied. Doses were kept below the concentration at which a nonspecific effect was seen, i.e., where fibrinogenolysis and major plasminogen consumption were observed. Small amounts of t-PA potentiated clot lysis by pro-UK by attenuating the lag phase characterist...