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)

The influence of enzyme or antiprogesterone antiserum treatment on the penetrability of rabbit ova was studied. Ova were recovered from oviducts, treated for varying periods of time with either trypsin, chymotrypsin, neuraminidase or antiprogesterone antiserum, and then transferred alone, or with control ova, to the oviducts of inseminated animals. 3 hours after transfer, they were recovered and examined for penetration of the vitellus and for the number of spermatozoa present in the perivitellum space or zona pellucida. Although no vitrelline penetration was observed in ova treated with the higher concentration of neuraminidase, the number of spermatozoa passing through the zona pellucida was not affected. Trypsin, chymotrypsin, and antiprogesterone antiserum treatment had only a slight effect on spermatozoic penetration of the zona pellucida and vitellus. There was no significant difference in ova penetrability between treated and control groups. It is concluded that trypsin and chymotrypsin do not affect any possible "fertilizin-like" substance of the ovum.
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PMID:The penetrability of rabbit ova treated with enzymes or anti-progesterone antibody: a probe into the nature of a mammalian fertilizin. 117 79

P-selectin on platelets and endothelial cells and E-selectin on endothelial cells are leukocyte receptors that recognize lineage-specific carbohydrates on neutrophils and monocytes. The proposed ligands for these receptors contain the Le(x) core and sialic acid. Since other investigators have shown that both E-selectin and P-selectin bind to sialylated Le(x), we evaluated whether E-selectin and P-selectin recognize the same counter-receptor on leukocytes. The interaction of HL60 cells with Chinese hamster ovary (CHO) cells expressing P-selectin or E-selectin was studied. To determine whether a protein component is required in addition to sialyl Le(x) for either P-selectin or E-selectin recognition, HL60 cells or neutrophils were digested with proteases, including chymotrypsin, elastase, proteinase Glu-C, ficin, papain, or thermolysin. Cells treated with these proteases bound E-selectin but not P-selectin. Fucosidase or neuraminidase treatment of HL60 cells markedly decreased binding to both E-selectin- and P-selectin-expressing CHO cells. Growth of HL60 cells in tunicamycin inhibited the ability of these cells to support P-selectin-mediated binding and, to a lesser extent, E-selectin-mediated binding. Purified P-selectin inhibited CHO:P-selectin binding to HL60 cells, but incompletely inhibited CHO:E-selectin binding to HL60 cells. However, purified soluble E-selectin inhibited CHO:P-selectin and CHO:E-selectin binding to HL60 cells equivalently and completely. COS cells, unable to bind to E-selectin or P-selectin, bound E-selectin but not P-selectin upon transfection with alpha-1,3-fucosyltransferase or alpha-1,3/1,4-fucosyltransferase. Similarly, LEC 11 cells expressing sialyl Le(x) bound E-selectin- but not P-selectin-expressing CHO cells. Sambucus nigra lectin, specific for the sialyl-2,6 beta Gal/GalNAc linkage, inhibited P-selectin but not E-selectin binding to HL60 cells. Although sialic acid and Le(x) are components of the P-selectin ligand and the E-selectin ligand, these results indicate that the ligands are related, having overlapping specificities, but are structurally distinct. A protein component containing sialyl Le(x) in proximity to sialyl-2,6 beta Gal structures on the P-selectin ligand may contribute to its specificity for P-selectin.
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PMID:P-selectin and E-selectin. Distinct but overlapping leukocyte ligand specificities. 137 36

Heparan sulfate binds to proteins present on the surface of Staphylococcus aureus cells. Binding of 125I-heparan sulfate to S. aureus was time dependent, saturable, and influenced by pH and ionic strength, and cell-bound 125I-heparan sulfate was displaced by unlabelled heparan sulfate or heparin. Other glycosaminoglycans of comparable size (chondroitin sulfate and dermatan sulfate), highly glycosylated glycoprotein (hog gastric mucin), and some anionic polysaccharides (dextran sulfate and RNA) inhibited heparan sulfate binding to various extents. Heat treatment (80 degrees C for 10 min) and treatment of the bacteria with pronase E, proteinase K, pepsin, and chymotrypsin considerably reduced their ability to bind 125I-heparan sulfate, but treatment with trypsin and neuraminidase did not affect binding. Scatchard plot analysis indicated the presence of cell surface components with low affinity (Kd = 3 x 10(-5) M) for heparan sulfate. Cell surface components were released by stirring bacteria with 1 M LiCl at 37 degrees C for 2 h. Proteins of this extract that competitively inhibited binding of 125I-heparan sulfate to S. aureus were isolated by affinity chromatography on heparin-Sepharose. Two proteins having molecular masses of approximately 66 and 60 kDa and the ability to bind 125I-heparan sulfate were obtained. The first 9 amino-terminal amino acid residues of the 66-kDa protein are Asp-Trp-Thr-Gly-Trp-Leu-Ala-Ala-Ala, and the first 4 amino-terminal amino acid residues of the 60-kDa protein are Met-Leu-Val-Thr.
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PMID:Binding of heparan sulfate to Staphylococcus aureus. 154 63

Monoamine oxidase B (MAO B) from pig liver has been reported to be a sialoglycoprotein. However, when that enzyme from pig lymphocytes and granulocytes was separated by polyacrylamide gel electrophoresis after labelling with the specific irreversible inhibitor [3H]pargyline, staining with 1-ethyl-2-[3-(1-ethyl-naphtho [1,2d] thiazolin-2-ylidene)-2-methylpropenyl] naphtho [1,2d] thiazolium bromide ("Stains-all") failed to detect the presence of sialic acid residues. Treatment of the enzyme in disrupted lymphocytes and granulocytes, or in mitochondrial fractions prepared from them, with neuraminidase resulted in a decrease in MAO activity. However, after the enzyme was rendered soluble by treatment with octylglucoside, treatment with neuraminidase had no effect on the activity. These results indicate that sialic acid residues are not an intrinsic component of MAO B, although associated material containing such groups appears to affect the activity of the membrane-bound enzyme. The activities of membrane-bound preparations of MAO B from pig lymphocytes and granulocytes were unaffected by treatment with trypsin or beta-chymotrypsin. After the preparations had been rendered soluble by treatment with octylglucoside there was a decrease in the activity on treatment with beta-chymotrypsin, but trypsin treatment had no effect. Thus solubilization resulted in residues sensitive to cleavage by the former enzyme becoming accessible to it. Tryptic and chymotryptic peptides separated from the sodium dodecyl sulphate denatured enzymes by polyacrylamide gel electrophoresis revealed no differences between MAO B prepared from lymphocytes and granulocytes.
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PMID:Investigations of the possible glycosylation of monoamine oxidase B from pig leucocytes. 167 8

Bursal (B) and thymic (T) lymphocytes from chickens sensitized to Mycobacterium tuberculosis (PPD) or human gamma globulin (hGG) produced an avian lymphocyte-inhibitory factor designated as LyIF-PPD or LyIF-hGG, respectively. A chemotactic factor (LCF) for peripheral blood leukocytes was elaborated only by T-cells sensitized to PPD and hGG. These factors were partially purified by HPLC and were characterized physiochemically. Maximum inhibitory activity for LyIF-PPD and LyIF-hGG occurred in peak fractions corresponding to molecular weight ranges of 29,000 to 52,000 daltons and 15,000 to 29,000 daltons, respectively. The inhibitory activity of B- and T-LyIF-hGG was lost after chymotrypsin and neuraminidase treatment. Maximum chemotactic activity for LCF-PPD and LCF-hGG was in peak HPLC fractions corresponding to molecular weight ranges of 9,000 to 16,000 daltons and 8,000 to 16,500 daltons, respectively. Chemotactic activity of LCF-PPD and LCF-hGG was lost following chymotrypsin treatment while it was not reduced after neuraminidase treatment. Both inhibitory and chemotactic activities were stable at 56 C for 30 min and resistant to changes in pH from 5 to 9. The precursor molecule for the lymphokine is made after antigen immunization, but activated in the presence of the sensitizing agent.
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PMID:Lymphocyte inhibitory and chemotactic factors produced by bursal and thymic lymphocytes. 169 44

We discovered an enzyme in human platelets that deamidates substance P and other tachykinins. Because an amidated carboxyl terminus is important for biological activity, we purified and characterized this deamidase. The enzyme, released from human platelets by thrombin, was purified to homogeneity by ammonium sulfate precipitation, followed by chromatography on an octyl-Sepharose column and chromatofocusing on PBE 94. The purified enzyme exhibits esterase, peptidase, and deamidase activities. The peptidase activity (with furylacryloyl-Phe-Phe) is optimal at pH 5.0 while the esterase (benzoyl-tyrosine ethyl ester) and deamidase (D-Ala2-Leu5-enkephalinamide) activities are optimal at pH 7.0. With biologically important peptides, the enzyme acts both as a deamidase (substance P, neurokinin A, and eledoisin) and a carboxy-peptidase (with bradykinin, angiotensin I, substance P-free acid, oxytocin-free acid) at neutrality, although the carboxypeptidase action is faster at pH 5.5. Enkephalins, released upon deamidation of enkephalinamides, were not cleaved. Gly9-NH2 of oxytocin was released without deamidation. Peptides with a penultimate Arg residue were not hydrolyzed. Some properties of the deamidase are similar to those reported for cathepsin A. The deamidase is inhibited by diisopropylfluorophosphate, inhibitors of chymotrypsin-type enzymes, and mercury compounds while other inhibitors of catheptic enzymes, trypsin-like enzymes, and metalloproteases were ineffective. In gel filtration, the native enzyme has an Mr = 94,000 while in non-reducing sodium dodecyl sulfate-polyacrylamide gel electrophoresis the Mr = 52,000 indicating it exists as a dimer. After reduction, deamidase dissociates into two chains of Mr = 33,000 and 21,000 as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. [3H]diisopropylfluorophosphate labeled the active site serine in the Mr = 33,000 chain. The first 25 amino acids of both chains were sequenced. They are identical with the sequences of the two chains of lysosomal "protective protein" which, in turn, has sequence similarity to the KEX1 gene product and carboxypeptidase Y of yeast. This protective protein complexes with beta-galactosidase and neuraminidase in lysosomes and is vitally important in maintaining their activity and stability. A defect in this protein is the cause of galactosialidosis, a severe genetic disorder. The ability of physiological stimuli (e.g. thrombin or collagen) to release the deamidase from platelets indicates that it may also be involved in the local metabolism of bioactive peptides.
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PMID:A peptidase in human platelets that deamidates tachykinins. Probable identity with the lysosomal "protective protein". 169 76

Transforming growth factor-beta (TGF-beta), a regulator of cell growth and differentiation, is secreted by most cultured cells in latent form (L-TGF-beta). Activation of L-TGF-beta can be achieved by various physico-chemical treatments, including acidification, alkalinization, heating and chaotropic agents. Proposed physiological activators include proteinases and glycosidases, which, however, only lead to limited activation (15-20% of the total TGF-beta activity after acidic activation). In the present study L-TGF-beta 1 partially purified from human platelets was not activated by treatment with neuraminidase or the proteinases plasmin, endoproteinase Arg-C, elastase and chymotrypsin. The mechanism of activation of L-TGF-beta was further assessed by using the human glioblastoma cell line 308, which releases biologically active TGF-beta 2. Factor(s) secreted by 308 glioblastoma cells were found to be able to activate partially purified L-TGF-beta 1 from human platelets. Our finding may prove to constitute a physiologically relevant mechanism for the activation of latent forms of TGF-beta in vivo.
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PMID:Activation of human platelet-derived latent transforming growth factor-beta 1 by human glioblastoma cells. Comparison with proteolytic and glycosidic enzymes. 183 Feb 5

During Plasmodium falciparum merozoite invasion into human and mouse erythrocytes, a 110-kDa rhoptry protein is secreted from the organelle into the erythrocyte membrane. In the present study our interest was to examine the interaction of rhoptry proteins of P. falciparum with the erythrocyte membrane. It was observed that the complex of rhoptry proteins of 140/130/110 kDa bind directly to a trypsin sensitive site on intact mouse erythrocytes, and not human, saimiri, or other erythrocytes. However, when erythrocytes were disrupted by hypotonic lysis, rhoptry proteins of 140/130/110 kDa were found to bind to membranes and inside-out vesicles prepared from human, mouse, saimiri, rhesus, rat, and rabbit erythrocytes. A binding site on the cytoplasmic face of the erythrocyte membrane suggests that the rhoptry proteins may be translocated across the lipid bilayer during merozoite invasion. Furthermore, pretreatment of human erythrocytes with a specific peptide derived from MSA-1, the major P. falciparum merozoite surface antigen of MW 190,000-200,000, induced binding of the 140/130/110-kDa complex. The rhoptry proteins bound equally to normal human erythrocytes and erythrocytes treated with neuraminidase, trypsin, and chymotrypsin indicating the binding site was independent of glycophorin and other major surface proteins. The rhoptry protein complex also bound specifically to liposomes prepared from different types of phospholipids. Liposomes containing PE effectively block binding of the rhoptry proteins to mouse cells, suggesting that there are two binding sites on the mouse membrane for the 140/130/110-kDa complex, one protein and a second, possibly lipid in nature. The results of this study suggest that the 140/130/110 kDa protein complex may interact directly with sites in the lipid bilayer of the erythrocyte membrane.
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PMID:Interaction of the 140/130/110 kDa rhoptry protein complex of Plasmodium falciparum with the erythrocyte membrane and liposomes. 188 71

Serine proteases, such as alpha-chymotrypsin or elastase, caused an aggregation of rat ascites tumour cell lines, AH-130, AH-109A and YS, in a protein free medium which preserved the cell viability. This aggregation, which was monitored spectrophotometrically, was dependent upon the protease activities and was resistant to treatment with either a calcium chelating reagent (EDTA) or neuraminidase. However, the tumour cell aggregates were redispersed by treatment with deoxyribonuclease I (DNase I). This dispersal effect was dependent upon the DNase activity. A possible relationship between the tumour cell aggregation and development of blood-borne metastasis was studied. An intravenous inoculation in rats of tumour cell aggregates performed by the alpha-chymotrypsin treatment resulted in significantly higher numbers of lung metastatic foci than an injection of single cells. When the re-separated single cells, prepared in vitro by treatment with DNase I following alpha-chymotrypsin treatment, were injected instead of the aggregates, the enhancement of metastasis was reversed. These enhancement and reversal effects were mimicked in vivo by intravenous injections of protease and nuclease following inoculation of a single cell suspension. That is, the number of metastatic foci caused by single cell inoculation followed by an intravenous alpha-chymotrypsin injection, was higher than that in a control group receiving PBS instead of alpha-chymotrypsin. Again, this augmentation was reversed by an injection of DNase I following alpha-chymotrypsin injection. Furthermore, an injection of DNase I alone itself reduced the starting number of metastases resulting from injection of the single tumour cell suspension. These data suggest that the metastatic behaviour of tumour cells may be increased by protease inducible DNA dependent cell aggregation should it occur in the blood stream.
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PMID:Serine protease-induced enhancement of blood-borne metastasis of rat ascites tumour cells and its prevention with deoxyribonuclease. 212 Dec 20

The present investigation explored the hypothesis that elevated levels of certain enzymes in the gingival crevicular environment of individuals with poor oral hygiene and/or gingival inflammation may modify the surfaces of epithelial cells and thereby modulate the types of bacteria which attach and colonize. Buccal epithelial cells treated with neuraminidase and certain proteases were used as a model for study. Bacteria studied included Streptococcus sanguis and Streptococcus mitis which have been associated with gingival health, Actinomyces species which are increased in plaque associated with developing gingivitis, and Bacteroides gingivalis, Bacteroides intermedius, and Actinobacillus actinomycetemcomitans which are associated with destructive periodontal diseases. Treatment of epithelial cells with the enzymes studied produced selective effects on their receptivity for bacteria. Neuraminidase treatment of epithelial cells greatly reduced the attachment of all strains of S. sanguis and S. mitis studied. In contrast, the number of Actinomyces viscosus, A. naeslundii and A. israelii cells which attached was significantly increased. Neuraminidase treatment also appeared to enhance attachment of B. intermedius and B. gingivalis. Treatment of buccal cells with trypsin, chymotrypsin or papain also selectively affected bacterial attachment. Such protease treatment greatly reduced the numbers of streptococci and A. viscosus cells which attached, while the numbers of B. gingivalis and B. intermedius were significantly increased. Treatment of epithelial cells with preparations of lysosomal enzymes derived from human PMNs produced similar selective effects. The changes in bacterial adhesion observed by the enzyme treatments studied are consistent with the shifts in the composition of the gingival crevice flora which occur when oral hygiene is terminated and gingivitis develops.
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PMID:Selective modulation of bacterial attachment to oral epithelial cells by enzyme activities associated with poor oral hygiene. 214 77


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