Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:3.4.21.1 (chymotrypsin)
10,938 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A 33-kD glycoprotein, known as the "prostate-specific antigen," was purified to homogeneity from human seminal plasma. The prostatic protein was identified as a serine protease, and its NH2-terminal sequence strongly suggests that it belongs to the family of glandular kallikreins. The structural protein of human seminal coagulum, the predominant protein in seminal vesicle secretion, was rapidly cleaved by the prostatic enzyme, which suggests that this seminal vesicle protein may serve as the physiological substrate for the protease. The prostatic enzyme hydrolyzed arginine- and lysine-containing substrates with a distinct preference for the former. All synthetic substrates tested were poor substrates for the enzyme. Synthetic Factor XIa substrate (pyro-glutamyl-prolyl-arginine-p-nitroanilide), and the synthetic kallikrein substrate (H-D-prolyl-phenylalanyl-arginine-p-nitroanilide) were hydrolyzed with maximum specific activities at 23 degrees C of 79 and 34 nmol/min per mg and Km values of 1.0 and 0.45 mM, respectively. Synthetic substrates for plasmin, chymotrypsin, and elastase were either not hydrolyzed by the enzyme at all, or only hydrolyzed very slowly.
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PMID:A kallikrein-like serine protease in prostatic fluid cleaves the predominant seminal vesicle protein. 390 93

Two trypsin inhibitors, CPPTI-I and CPPTI-II of Mr 3 250 and 7 850, respectively, were isolated from resting white bush seeds. Both inhibitors are cysteine-rich proteins. In addition to trypsin, they inhibit a trypsin-like enzyme isolated from Streptomyces griseus proteinase but they do not act on chymotrypsin, kallikrein or subtilopeptidase A. The isolated inhibitors contain a lysine residue in position P1 of the reactive site.
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PMID:Isolation of two trypsin inhibitors from resting seeds of the white bush (Cucurbita pepo var. patissonina) and their properties. 393 88

1. The effect of age and androgen level on enzyme activity and cellular structure has been determined in the mouse submaxillary gland.2. A new protease which resembles chymotrypsin in its substrate specificity has been characterized in the gland.3. Activity of the chymotrypsin- and trypsin-like proteases and renin increased considerably in male mice concomitantly with proliferation of granules in the secretory tubules of the gland.4. The androgen dependence of the chymotrypsin- and trypsin-like enzymes, renin and the organelles within the secretory tubules was confirmed in castrated male mice. The activity of these enzymes increased and correlated with the appearance of intracellular granules in the secretory tubules when the castrated male mice and in addition female mice were treated with testosterone preparations.5. Kallikrein, a closely related protease, and amylase increased in activity with age but showed no sex-linked differences.6. The results suggest that kallikrein is sequestered in acinar cells whereas the androgen-dependent enzymes (chymotrypsin, trypsin and renin) are located in the secretory tubules.
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PMID:The influence of androgens on enzymes (chymotrypsin-and trypsin-like proteases, renin, kallikrein and amylase) and on cellular structure of the mouse submaxillary gland. 476 1

One of the striking features of the proteolytic enzymes as a group is the immense variety of biological functions served by enzymes employing one of a few basic mechanisms. For example, in the higher animals, enzymes for activation of zymogens (trypsin), for digestion of dietary proteins (trypsin, chymotrypsin, elastase), for blood clotting (thrombin), for clot lysis (plasmin), and for sensing pain (kallikrein) all appear to use the same mechanism and to have evolved from the same ancestral gene by the process of gene duplication and subsequent divergent evolution. Equally striking is the variety of chemical solutions of the same functional problem, such as the peptide-bond cleavage by sulfhydryl proteases on the one hand and serine proteases on the other.
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PMID:Evolution of structure and function of proteases. 486 30

Bioactive polypeptides have been isolated from three sea anemone species by gel filtration and ion-exchange chromatography: hemolysins from Gyrostoma helianthus and Radianthus koseirensis and proteinase inhibitors from the latter species and from Rhodactis rhodostoma. The hemolysins (molecular weight about 10,000) are free of phospholipase A activity, possess considerable ichthyotoxicity, and hemolysis is inhibited by sphingomyelin. The main proteinase inhibitor from Rhodactis rhodostoma is composed of 48 amino acids and inhibits trypsin, kallikrein and chymotrypsin, whereas the semipure inhibitor from Rhadianthus koseirensis has very low affinity for serine proteases and does not inhibit chymotrypsin.
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PMID:Hemolysins and proteinase inhibitors from sea anemones of the Gulf of Aqaba. 613 55

The development of dysenteric intoxication in rabbits led to an abrupt increase in the blood activity of proteolytic enzymes. This increase was accompanied by the reduced content of alpha 1-antitrypsin, and that of rapid and slow kallikrein inhibitor. Meanwhile there occurred a remarkable decrease in blood serum ability to bind chymotrypsin and kallikrein, and diminution of alpha 2-macroglobulin level. Trypsin, binding by blood serum did not undergo any substantial changes. In these conditions, the permeability of pulmonary vessels drastically rose and surface activity of the washing off dropped. The pathomorphological alterations in the lungs corresponded with the appearance of the "shock lung". Contrykal normalized the blood content of proteolytic enzymes and inhibitors, as well as that of the bronchoalveolar washing off, averted the development of gross pathomorphological alterations, exerting no appreciable effect on the surface activity of the bronchoalveolar washing off.
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PMID:[Effect of kontrikal on the activity of proteolytic enzymes and their inhibitors in blood, state of the bronchoalveolar secretion and the nature of the lung damage in dysenteric intoxication]. 617 53

Four protein protease inhibitors (I, II, III, IV) having low molecular weights (10 600-6500) and basic isoelectric points were isolated by affinity chromatography from bovine spleen. Inhibitor IV was identified as the basic pancreatic trypsin inhibitor (Kunitz inhibitor); the presence and distribution of components I, II and III vary in the different bovine organs. Spleen inhibitors I, II, III and IV were purified by ion-exchange chromatography; they form 1:1 complexes with trypsin and inhibit enzymatic activity of trypsin, chymotrypsin and kallikrein. Inhibitors I, II and III contain carbohydrate moieties (7-4%) covalently bound to the polypeptide chain. Specific basic pancreatic trypsin inhibitor antiserum has shown the complete identity between inhibitor IV and the basic pancreatic trypsin inhibitor, while partial cross-reactivity between the basic pancreatic trypsin inhibitor and inhibitors I, II and III can be seen from a double immunodiffusion test.
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PMID:Heterogeneity of the basic pancreatic inhibitor (Kunitz) in various bovine organs. 618 88

Blood serum separation by the method of gel filtration on Sephadex G-200 with the subsequent immunochemical determination of the quantitative content of basic proteolysis inhibitors permitted isolating the alpha 2-macroglobulin fraction while alpha 1-antitrypsin and alpha 1-antichymotrypsin separation was a failure. The immunochemical analysis of the antienzymic activity of the isolated inhibitors showed that 32.3 +/- 3.5% of the introduced kallikrein, 18.7 +/- 0.6% of trypsin and 14.4 +/- 4.1% of chymotrypsin were bound in the zone of alpha 2-macroglobulin. The rest of antienzymic activity was localized in the zone of alpha 1-antitrypsin and alpha 1-antichymotrypsin. After a preliminary saturation of blood serum with trypsin in the amount equivalent to its antitryptic capacity (200 micrograms/ml) the ability of alpha 2-macroglobulin to bind kallikrein and chymotrypsin lowers considerably (by 69 and 72%, respectively). In the zone of alpha 1-antitrypsin and alpha 1-antichymotrypsin a decrease in the ability to bind kallikrein and chymotrypsin amounted to 44 and 12% respectively. Thus, alpha 2-macroglobulin being bound with trypsin looses considerably its ability to bind other enzymes.
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PMID:[Antiproteinase activity of alpha 2-macroglobulin]. 620 37

To further characterize the properties of the potent natriuretic and diuretic substance that can be extracted from atrial tissue, we investigated its susceptibility to inactivation by kallikrein and other proteolytic enzymes. Extracts of rat atrial tissue (tissue wet wt 100 mg/ml) were incubated with enzymes under standard conditions and tested by injection into nondiuretic anesthetized rats. One hour of incubation at 37 degrees C with pure porcine pancreatic kallikrein at concentrations of 250 micrograms/ml or greater significantly reduced the activity of atrial natriuretic substance. The reduction in activity was dependent on both enzyme concentration and time of incubation. The kallikrein-catalyzed degradation was completely blocked by aprotinin but was only partially retarded by soybean trypsin inhibitor. Trypsin reduced natriuretic and diuretic activity of extracts at concentrations of 400 micrograms/ml or greater, with nearly complete inactivation at a concentration of 1,000 micrograms/ml. Carboxypeptidase B also caused a concentration-dependent inactivation of the natriuretic material. Last, alpha-chymotrypsin (1,000 micrograms/ml) and elastase (1,000 micrograms/ml) were found to destroy the natriuretic activity. In a separate set of experiments natriuretic activity was observed to be retained by a 1,000 mol wt cutoff membrane. Inactivation of the natriuretic peptide by renal kallikrein is a possible mechanism for in vivo regulation of natriuretic activity.
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PMID:Inactivation of atrial natriuretic substance by kallikrein. 623 96

1. DNase I from porcine pancreas, if Mg2+ was present, hydrolyzed both sDNA and dDNA, whether free or bound to Sepharose. The hydrolysis rates were maximum at pH 7.5 with the bound DNAs and at pH 7.0 with the free DNAs negligible at pH 4.0 and pH 10.5 with the free and bound DNAs. The hydrolysis was completely inhibited by 50 mM sodium citrate. 2. With 50 mM citrate buffer (Ph 4.0), DNase I was effectively adsorbed on the DNA-Sepharoses in the absence of 5 mM Mg2+. The adsorbed enzyme was effectively eluated by the buffer containing 1 M KCl (eluate). The amounts of the eluated enzyme were approximately 1.5 X 10(5) units/mg DNA with sDNA-Sepharose and approximately 3.0 X 10(5) units/mg DNA with dDNA-Sepharose. This simple adsorption-elution of the pancreas extract resulted in approximately 300-fold purification of DNase I with a yield of 95%. In the elute, the ratios in activity of trypsin, chymotrypsin and RNase to DNase I were 1/(4.0 X 10(5)), 1/(5.3 X 10(3)), and 1/(4.1 X 10(2)) as low as in the extract, respectively. In addition, the eluate was not contaminated by kallikrein or carboxypeptidases A and B. 3. Upon repeating the adsorption-elution described above, the adsorbing capacities of DNA-Sepharoses gradually deteriorated with the whole pancreas extract, but not with the precipitate of the extract formed on 60% ammonium sulfate saturation, which contained 90% of the DNase I. With the precipitate, one dDNA-Sepharose solumn was repeatedly usable at least 20-times without deterioration. The DNase I preparation thus obtained was homogeneous on SDS-polyacrylamide gel electrophoresis. 4. Conceivably, the above-mentioned adsorption of DNase I on DNA-Sepharoses was mainly due to the steric and electrostatic affinity of a relatively large moiety of the DNA molecule to the substrate-binding site, but not to the catalytic site, of the enzyme.
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PMID:Affinity chromatography of porcine pancreas deoxyribonuclease I on DNA-binding sepharose under non-digestive conditions, using its substrate-binding site. 625 6


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