Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.4.21.5 (thrombin)
 33,306 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Guanidinophenyl derivatives of pyrazole have been synthesized. Their inhibitory effects on (i) bovine trypsin, bovine thrombin, porcine pancreatic kallikrein catalyzed hydrolysis of p-nitro anilide of N alpha -benzoyl-arginine and (ii) blood coagulation and platelet aggregation, were investigated. The kinetic behaviour of all compounds conformed to that of a reversible competitive inhibition pattern, and they were also found to act in vitro as inhibitors of platelet aggregation induced by ADP.
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PMID:Guanidinophenyl derivatives of pyrazole: synthesis and inhibitory effect on serine proteinases, blood coagulation and platelet aggregation. 353 35

An inactive form of human urinary kallikrein (inactive HUK) was highly purified from fresh urine collected from healthy men. Inactive HUK was separated from the active kallikrein (HUK) initially presents in the urine by affinity chromatography on a column of aprotinin immobilized on Sepharose 4B and further purified by gel filtration, ion-exchange chromatography and immunoaffinity chromatography on an anti-HUK antibody immobilized Sepharose 4B column. Inactive HUK was rapidly activated by a trace amount of trypsin. While, plasmin, urokinase, thrombin and chymotrypsin caused no activation of inactive HUK. The molecular weights of inactive HUK and HUK were estimated to be 4.8 X 10(4) and 4.5 X 10(4), respectively. The molecular weight of active HUK generated from inactive HUK by the action of trypsin (HUK'') was almost the same as that of HUK. The mobility of inactive HUK was slightly slower than that of HUK on both immunoelectrophoresis and polyacrylamide gel disc electrophoresis. On the other hand, the electrophoretic mobility of HUKK'' was almost the same as that of HUK. These two types of active HUK had no significant difference in the Km values for H-Pro-Phe-Arg-MCA hydrolysis and inhibition profiles by various protease inhibitors and anti-HUK antibody. Inactive HUK was unable to be measured by the direct radioimmunoassay (RIA) but HUK" generated by the action of trypsin could be measured by the RIA.
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PMID:An inactive form of kallikrein in human urine. 354 16

Determination of the nucleotide sequence of a cDNA for batroxobin, a thrombin-like enzyme from Bothrops atrox, moojeni venom, allowed elucidation of the complete amino acid sequence of batroxobin for the first time for a thrombin-like snake venom enzyme. The molecular weight of batroxobin is 25,503 (231 amino acids). The amino acid sequence of batroxobin exhibits significant homology with those of mammalian serine proteases (trypsin, pancreatic kallikrein, and thrombin), indicating that batroxobin is a member of the serine protease family. Based on this homology and enzymatic and chemical studies, the catalytic residues and disulfide bridges of batroxobin were deduced to be as follows: catalytic residues, His41, Asp86, and Ser178; and disulfide bridges, Cys7-Cys139, Cys26-Cys42, Cys74-Cys230, Cys118-Cys184, Cys150-Cys163, and Cys174-Cys199. The amino-terminal amino acid residue of batroxobin, valine, is preceded by 24 amino acids. This may indicate that the amino-terminal hydrophobic peptide (18 amino acids) is a prepeptide and that the hydrophilic peptide (6 amino acids), preceded by the putative prepeptide, is a propeptide.
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PMID:Molecular cloning and sequence analysis of cDNA for batroxobin, a thrombin-like snake venom enzyme. 354 2

Monoclonal antibodies to purified human urinary kallikrein have been developed. Selection of antibody producing clones was based on 125I-kallikrein binding activity of hybridoma media in both radioimmunoassay and enzyme-linked immunosorbent assay. Three clones (2 IgG1, 1 IgG2b) were subcloned, characterized, and compared with the polyclonal antiserum generated in rabbits immunized with the purified kallikrein. With radioimmunoassay, mouse ascitic fluids or rabbit antisera dilutions showing 50% binding to 125I-kallikrein were 1:1.2 X 10(6) (E7A9), 1:1.2 X 10(5) (H6A6), 1:8.0 X 10(4) (E12H1), and 1:1.4 X 10(6) (the rabbit antisera). With enzyme-linked immunosorbent assay, mouse ascitic fluids from clones E7A9 and H6A6 showed half-maximal absorbance at dilutions of 1:2.1 X 10(5) and 1:1.0 X 10(5) respectively, and the polyclonal antiserum showed half-maximal absorbance at a dilution of 1:2.0 X 10(4). These monoclonal antibodies showed no cross-reactivity with rat tissue kallikrein, rat urinary plasminogen activator, or dog pancreatic kallikrein, while the polyclonal antiserum showed some cross-reactivity. The binding of monoclonal or polyclonal antibodies to 125I-human urinary kallikrein was not affected by human plasma kallikrein, thrombin, or urokinase in a competitive radioimmunoassay. By using purified human urinary kallikrein immobilized to agarose, antibodies produced by clones E7A9 and H6A6 and in the rabbit antisera were purified to homogeneity. Each of these affinity-purified antibodies inhibited the esterase activity, and two of the three inhibited the kininogenase activity, of human urinary kallikrein. A sandwich immunosorbent assay was developed to measure this kallikrein using monoclonal antibody from the clone E7A9 in conjunction with the polyclonal antibodies.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Characterization of monoclonal and polyclonal antibodies to human tissue kallikrein. 385 80

1. The inhibition by suramin of complement components, and of blood clotting, fibrinolytic, and plasma kinin forming factors depended on the conditions of the assay and on the substrates used.2. Haemolysis by complement was more effectively inhibited in red blood cell suspensions, than in agarose gel plates. In esterolytic tests, the activation of component 1 (C1) to C1 esterase was significantly inhibited by 0.1-0.3 mM suramin, and the activity of C1 esterase by 0.5 mM suramin.3. Part of the anticoagulant effect of suramin is due to inhibition of the action of thrombin on fibrinogen.4. Suramin did not inhibit fibrin degradation by the fibrinolytic system in plasma. In esterolytic tests, the activation of plasminogen was more potently inhibited than the activity of plasmin.5. Activation of plasma kallikrein, measured either by kinin formation or by esterolysis, was inhibited by 0.1-0.3 mM suramin. Active plasma kallikrein was inhibited by 0.3-0.5 mM suramin. Pancreatic kallikrein was weakly inhibited, and urinary kallikrein not at all.
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PMID:Effects of suramin on complement, blood clotting, fibrinolysis and kinin formation. 478 38

p-Guanidinobenzoate derivates were prepared and their inhibitory effects on trypsin, plasmin, pancreatic kallikrein, plasma kallikrein, thrombin, C1r and C1 esterase were examined. Among the various inhibitors tested, 6'-amidino-2-naphthyl-4-guanidinobenzoate dihydrochloride, 4-(beta-amidinoethenyl)phenyl-4-guanidinobenzoate dimethanesulfonate and 4-amidino-2-benzoylphenyl-4-guanidinobenzoate dimethanesulfonate were the most effective inhibitors of trypsin, plasmin, pancreatic kallikrein. plasma kallikrein and thrombin and they strongly inhibited the esterolytic activities of C1r and C1 esterase, and then strongly inhibited complement-mediated hemolysis.
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PMID:New synthetic inhibitors of C1r, C1 esterase, thrombin, plasmin, kallikrein and trypsin. 627 Dec 24

Fluorogenic peptides, peptidyl-4-methylcoumaryl-7-amides (MCA), containing COOH-terminal lysine residues, were newly synthesized and tested as substrates for plasmin. Among six peptidyl-MCA's, Boc-Val-Leu-Lys-MCA and Boc-Glu-Lys-Lys-MCA were found to be useful for the specific and sensitive assay of plasmin. The Km values estimated from Line-weaver-Burk plots for these substrates using human and bovine plasmins were in the region of 10(-4) M. Boc-Glu-Lys-Lys-MCA was slightly hydrolyzed by bovine plasma kallikrein, and Boc-Val-Leu-Lys-MCA was slightly hydrolyzed by human and hog urinary kallikreins and hog pancreatic kallikrein. However, both of the fluorogenic peptides were essentially unaffected by urokinase, alpha-thrombin, Factor Xa, Factor IXa, Factor XIa, and Factor XIIa. It was confirmed that plasmin hydrolyzed Boc-Glu-Lys-Lys-MCA, cleaving the lysyl-MCA bond, but not the lysyl-lysyl bond. These fluorogenic peptides were resistant to human plasmin activated by streptokinase. Boc-Glu-Lys-Lys-MCA was not hydrolyzed by human plasmin or plasminogen in the presence of more than a 5-fold molar excess of streptokinase. The sensitivity of Boc-Val-Leu-Lys- of more than a 5-fold molar excess of streptokinase. The sensitivity of Boc-Val-Leu-Lys-MCA to human plasmin was also reduced, but plasmin retained 35% of the maximum activity even in the presence of a 20-fold molar excess of streptokinase. These results suggest that streptokinase-plasmin complex has essentially no activity towards Boc-Glu-Lys-Lys-MCA.
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PMID:New fluorogenic peptide substrates for plasmin. 644 93

The purpose of this study was to determine the distribution and characteristics of kinin-generating proteases (kininogenases) in rat pituitary tissue. Male rat pituitaries were dissected into their various lobes, sonicated in saline containing 12 mM deoxycholic acid, and assayed for protease activity at pH 8.5 using kininogen and chromogenic peptide substrates; kinin generation was measured by RIA. The rat pituitary was found to contain kininogenase activity highly concentrated in the pars intermedia; this activity was strongly inhibited by aprotinin and was resistant to soybean trypsin inhibitor. Antiserum against rat urinary kallikrein also inhibited the intermediate pituitary kininogenase. The kininogenase product was identified as bradykinin by reversed-phase high performance liquid chromatography. Homogenization of neurointermediate pituitaries in 0.25 M sucrose buffer (pH 7.5) followed by differential centrifugation (1,000 X g, 5 min; 10,000 X g, 20 min; 105,000 X g, 70 min) demonstrated that most of the kininogenase activity was in the 10,000 X g pellet. Kinin generation by neurointermediate pituitary extracts had a pH optimum of 8.0, and such extracts also hydrolyzed chromogenic peptide substrates for kallikreins. In addition, neurointermediate pituitary extracts were found to contain a distinct protease which hydrolyzed a chromogenic peptide substrate for thrombin. The intermediate pituitary kininogenase resembles glandular kallikrein and possibly may participate in prohormone processing.
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PMID:A kininogenase resembling glandular kallikrein in the rat pituitary pars intermedia. 655 May 32

Mono-halo derivatives of 1,3-di-(p-amidinophenoxy)-2,2-bis-(p-amidinophenoxymethyl)p ropane (TAPP-H) have been synthesized and their inhibitory effect on the bovine trypsin, bovine thrombin and porcine pancreatic kallikrein catalyzed hydrolysis of p-nitroanilides of amino acids was investigated, at pH 8.1 and 37 degrees, in parallel with that of TAPP-H and benzamidine. The addition of a halogen (Cl, Br or I) at position 2 of each benzamidine moiety of TAPP-H is accompanied by an increase of the inhibitory effect. This is especially evident in the case of porcine pancreatic kallikrein inhibition by TAPP-Cl. The structural basis of the different inhibitory effect of TAPP-H, TAPP-halo derivatives and benzamidine on the catalyzed hydrolysis of the proteinases examined are discussed and the role of Asp-189 in bovine trypsin, Asp-189 and Glu-149 or Asp-192 in bovine thrombin and Asp-189 and Asp-A148 or Glu-150 in porcine pancreatic kallikrein is focused.
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PMID:Aromatic tetra-amidines: synthesis of halo-derivatives and their antiproteolytic activity. 656 42

4-Substituted carbonylphenyl ester derivatives were prepared and their inhibitory effects on chymotrypsin, trypsin, thrombin, plasmin, pancreatic kallikrein, and plasma kallikrein were examined. Among the various inhibitors tested, 4-[2-(dimethylamino)ethylaminocarbonyl]phenyl 1,2,3,4-tetrahydro-1-naphthoate hydrochloride (FK-316), 4-[(2-[4-pyrrolidinocarbonylmethyl)oxycarbonyl]-phenyl 5-methoxyindole-3-acetate dihydrochloride (FK-375), 4-[(2-[4-(piperidinocarbonylmethylpiperadino]ethyl)oxycarbonyl+ ++]phenyl 1-naphthylacetate dihydrochloride (FK-386), 4-[(2-[4-(2-[morpholino]ethyl)piperadino]ethyl)oxycarbonyl]p henyl 5-methoxy-2-methylindole-3-acetate trihydrochloride (FK-401) and 4-(4-isopropylpiperadinocarbonyl)phenyl 1,2,3,4-tetrahydro-1-naphthoate methanesulfonate (FK-448) were the most effective and specific inhibitors of chymotrypsin.
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PMID:New synthetic inhibitors of chymotrypsin. 671 1


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