Mixed Inhibition of cPEPCK by Genistein, Using an Extended Binding Site Located Adjacent to Its Catalytic Cleft

SummaryWe examined the effect of the synthetic pentasaccharide representing the minimal binding site of heparin to antithrombin on the antithrombin-mediated inactivation of factor Vila bound to tissue factor. This effect was compared to the effect of unfractionated heparin. Using purified recombinant human coagulation factors and either a clotting or an amidolytic assay for the determination of the residual activity of factor Vila, we showed that the pentasaccharide was an efficient antithrombin-dependent inhibitor of the coagulant activity of tissue factor-factor Vila complex. In our experimental conditions, assuming a mean MW of 14,000 for heparin, the molar pseudo-first order rate constants for ATIII-mediated FVIIa inhibition by ATIII-binding heparin and by the synthetic pentasaccharide were found to be similar with respective values of 104,000 ± 10,500 min-1 and 112,000 ± 12,000 min-1 (mean ± s.e.m., n = 3)

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Localization of a Vitronectin Binding Region of Plasminogen Activator Inhibitor-1

Thrombosis and Haemostasis ◽

10.1055/s-0038-1653876 ◽

1995 ◽

Vol 73 (05) ◽

pp. 829-834 ◽

Cited By ~ 11

Author(s):

Jaya Padmanabhan ◽

David C Sane

Keyword(s):

Binding Site ◽

Plasminogen Activator ◽

Inhibitory Activity ◽

Plasminogen Activator Inhibitor ◽

Structural Homology ◽

Binding Region ◽

Plasminogen Activator Inhibitor 1 ◽

Activator Inhibitor ◽

Pai 1

SummaryThe PAI-1 binding site for VN was studied using two independent methods. PAI-1 was cleaved by Staph V8 protease, producing 8 fragments, only 2 of which bound to [125I]-VN. These fragments were predicted to overlap between residues 91-130. Since PAI-2 has structural homology to PAI-1, but does not bind to vitronectin, chimeras of PAI-1 and PAI-2 were constructed. Four chimeras, containing PAI-1 residues 1-70,1-105,1-114, and 1-167 were constructed and expressed in vitro. PAI-1, PAI-2, and all of the chimeras retained inhibitory activity for t-PA, but only the chimera containing PAI-1 residues 1-167 formed a complex with VN. Together, these results predict that the VN binding site of PAI-1 is between residues 115-130.

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Enhancement of Plasminogen Binding to U937 Cells and Fibrin by Complestatin

Thrombosis and Haemostasis ◽

10.1055/s-0038-1655921 ◽

1997 ◽

Vol 77 (01) ◽

pp. 137-142 ◽

Cited By ~ 20

Author(s):

Kiyoshi Tachikawa ◽

Keiji Hasurni ◽

Akira Endo

Keyword(s):

Binding Site ◽

Binding Affinity ◽

Blood Cells ◽

Aminocaproic Acid ◽

U937 Cells ◽

Biochemical Basis ◽

Equilibrium Binding ◽

Pharmacological Stimulation ◽

Endogenous Fibrinolysis ◽

Stimulation Of

SummaryPlasminogen binds to endothelial and blood cells as well as to fibrin, where the zymogen is efficiently activated and protected from inhibition by α2-antiplasmin. In the present study we have found that complestatin, a peptide-like metabolite of a streptomyces, enhances binding of plasminogen to cells and fibrin. Complestatin, at concentrations ranging from 1 to 5 μM, doubled 125I-plasminogen binding to U937 cells both in the absence and presence of lipoprotein(a), a putative physiological competitor of plasminogen. The binding of 125I-plasminogen in the presence of complestatin was abolished by e-aminocaproic acid, suggesting that the lysine binding site(s) of the plasminogen molecule are involved in the binding. Equilibrium binding analyses indicated that complestatin increased the maximum binding of 125I-plasminogen to U937 cells without affecting the binding affinity. Complestatin was also effective in increasing 125I-plasminogen binding to fibrin, causing 2-fold elevation of the binding at ~1 μM. Along with the potentiation of plasminogen binding, complestatin enhanced plasmin formation, and thereby increased fibrinolysis. These results would provide a biochemical basis for a pharmacological stimulation of endogenous fibrinolysis through a promotion of plasminogen binding to cells and fibrin.

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Regulation of the CD95 gene by the p53 family network- the intronic binding site is essential

Zeitschrift für Gastroenterologie ◽

10.1055/s-2008-1037533 ◽

2008 ◽

Vol 46 (01) ◽

Author(s):

AE Schulze Schleithoff ◽

A Kairat ◽

AF Koch ◽

W Stremmel ◽

PH Krammer ◽

...

Keyword(s):

Binding Site ◽

P53 Family ◽

Family Network

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ASSOCIATION BEHAVIOUR OF THE OESTRADIOL-BINDING PROTEIN COMPLEX WITH THE NUCLEAR FRACTION

Acta Endocrinologica ◽

10.1530/acta.0.071s420 ◽

1972 ◽

Vol 71 (2_Suppla) ◽

pp. S420-S438 ◽

Cited By ~ 6

Author(s):

David L. Williams ◽

Jack Gorski

Keyword(s):

Binding Site ◽

Protein Complex ◽

Binding Protein ◽

Nuclear Fraction ◽

Site Saturation ◽

Total Binding

ABSTRACT A number of studies have been carried out to examine the distribution of the oestradiol-binding protein complex between cytosol and nuclear fractions as a function of total binding site saturation. The results of these studies suggest that each binding protein has one binding site for the hormone. In addition, these studies suggest that the interaction of the oestradiol-binding protein complex with the nucleus involves a large number of low affinity association sites.

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Anti-thyrotrophin receptor antibodies in Graves' disease as demonstrated directly by immunoprecipitation assay

Acta Endocrinologica ◽

10.1530/acta.0.1020049 ◽

1983 ◽

Vol 102 (1) ◽

pp. 49-56 ◽

Cited By ~ 8

Author(s):

Tjerk W. A de Bruin ◽

Daan van der Heide ◽

Maria C. Krol

Keyword(s):

Binding Site ◽

Tsh Receptor ◽

Graves Disease ◽

Immunoprecipitation Assay ◽

Receptor Complexes ◽

Auto Antibody ◽

Receptor Antibodies ◽

Normal Controls

Abstract. An immunoprecipitation assay was developed to determine the presence of antibodies against human TSH1 receptors. With this assay we were able to demonstrate that in comparison with sera from normal controls, 24 out of 30 (80%) sera from patients with untreated Graves' disease could immunoprecipitate more [125I]TSH-TSH receptor complexes. In 9 assays, an average of 14.1 ± 3.7% (sd) of the [125I]TSH-TSH receptor complexes was immunoprecipitated by the 30 Graves' sera vs 9.8 ± 3.0% by the normal pool serum (n = 23) (P < 0.001) and 7.7 ± 2.8% by the 22 normal sera (P < 0.001). One serum of the 24 positive Graves' sera was studied in detail. The results suggest that this serum contained an anti-TSH receptor auto-antibody directed towards a different determinant on the TSH receptor than the TSH binding site.

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