Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.4.22.32 (bromelain)
 1,025 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The protease isolated jawasee shrub was found to hydrolyze egg albumin, casein, haemoglobin and gelatin optimally near neutral pH. Fibrin, bovin serum albumin, skin albumin and skin mucoids were hydrolyzed at slightly alkaline pH, while skin globulins were hydrolyzed at slightly acidic pH. The enzyme had no effect of fibrous collagen. The optimum conditions for the hydrolysis of 50 mg of egg albumin were found to be 50 mg of alhagain at pH 6.0 and 45 degrees C for 30 minutes. A Km value of 4.4 X 10(-3) M was obtained from the Lineweaver-Burk plot for the hydrolysis of egg albumin. The enzyme was found to be comparatively thermostable and was most stable at pH 4.7. Ultraviolet irradiation exhibited no appreciable effect on the enzyme activity. The ultraviolet absorption spectrum of alhagain in bi-distilled water resembles those of bromelain and trypsin. The sugar-containing enzyme was found to have a molecular weight of 20,650. The enzymeconsists of 189 amino acid residues per molecule, neutral and acidic amino acids being present in high concentrations. The partial specific volume of alhagain was calculated to be 0.743 ml/g from its amino acid composition. Phenylalnine and arginine formed the amino terminal amino acids of alhagain, while aspartic acid and serine were identified as its carboxy terminal amino acids. Results are discussed with relation to other plant proteases.
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PMID:Studies on the physico-chemical properties of alhagain. 2 Nov 47

We have observed that treatment of rabbit synovial fibroblasts with proteolytic enzymes can induce secretion of collagenase (EC 3.4.24.7) and plasminogen activator (EC 3.4.21.-). Cells treated for 2-24 hr with plasmin, trypsin, chymotrypsin, pancreatic elastase, papain, bromelain, thermolysin, or alpha-protease but not with thrombin or neuraminidase secreted detectable amounts of collagenase within 16-48 hr. Treatment of fibroblasts with trypsin also induced secretion of plasminogen activator. Proteases initiated secretion of collagenase (up to 20 units per 10(6) cells per 24 hr) only when treatment produced decreased cell adhesion. Collagenase production did not depend on continued presence of proteolytic activity or on subsequent cell adhesion, spreading, or proliferation. Routine subculturing with crude trypsin also induced collagenase secretion by cells. Secretion of collagenase was prevented and normal spreading was obtained if the trypsinized cells were placed into medium containing fetal calf serum. Soybean trypsin inhibitor, alpha(1)-antitrypsin, bovine serum albumin, collagen, and fibronectin did not inhibit collagenase production. Although proteases that induced collagenase secretion also removed surface glycoprotein, the kinetics of induction of cell protease secretion were different from those for removal of fibronectin. Physiological inducers of secretion of collagenase and plasminogen activator by cells have not been identified. These results suggest that extracellular proteases in conjunction with plasma proteins may govern protease secretion by cells.
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PMID:Proteases induce secretion of collagenase and plasminogen activator by fibroblasts. 20 72

A preliminary experiment showed that the supernatants of in vitro cultured peritoneal cells (rich in Ly-1 B cell subset shown to secrete most IgM autoantibodies against bromelain-treated mouse red blood cells (BrMRBC) and DNA) from different mouse strains did not contain any significant antibody activity against DNA and cytoskeleton proteins, although the presence of anti-BrMRBC antibodies was clearly evident. Therefore, we investigated comparative natural antibody (NAb) specificities against an antigen panel (DNA, cytoskeleton proteins, IgG, bovine serum albumin (BSA), BrMRBC, trinitrophenyl (TNP), and trimethylammonium (TMA) haptens) among Ig-secreting hybridoma collections from the splenic (158) and peritoneal (230) immune compartments of autoimmune New Zealand black (NZB) and lipopolysaccharide (LPS)-stimulated BALB/c mice. The data showed: (i) isotypic restriction (mu and gamma 3 only), predominance of TMA ion-reactive (including BrMRBC) but negligible anti-DNA-reactive antibody specificities, and lack of simultaneous polyspecific widespread reactivity (i.e. at least four or more antigens) against DNA and cytoskeleton proteins in the peritoneal cavity; (ii) predominance of simultaneous widespread polyspecific reactivity against DNA and cytoskeleton proteins but negligible or no TMA hapten-reactive antibody specificities in the spleen. These observations reflect certain differences in the B cell repertoire of peritoneal cavity (rich in Ly-1 B cells) compared with spleen. The NAb against BrMRBC and those reactive with DNA and cytoskeleton proteins, which have been suggested to be secreted by the Ly-1 B cell subset, are distinguishable on the basis of the presence of separate recurrent idiotypes and preferential localization of B lymphocytes directed against these autoantigens.
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PMID:Comparative analysis of natural antibody specificities among hybridomas originating from spleen and peritoneal cavity of adult NZB and BALB/c mice. 325 8

The effect of the diterpene forskolin on vascular permeability alone and in combination with bradykinin, prostaglandin E1, adenosine or histamine has been investigated in rats. Vascular permeability in rat skin was measured using [125I]-labelled bovine serum albumin ([125I]BSA) as a tracer. In addition, the effect of forskolin on footpad edema induced by the injection of a mixture of 2% carrageenin was determined. Forskolin caused a marked potentiation of the increase in vascular permeability in rat skin elicited by the intradermal injection of histamine or bradykinin. However, forskolin caused a significant suppression of the prostaglandin E1-induced vascular permeability response and at a low concentration suppressed the response to adenosine. Forskolin greatly potentiated the footpad edema induced with carrageenin in rats. Intravenous administration of the enzyme bromelain, which reduces plasma kininogen levels, inhibited the footpad edema induced with carrageenin or with a mixture of carrageenin and forskolin. Parenteral administration of a prostaglandin synthetase inhibitor, indomethacin, suppressed the footpad edema induced with carrageenin, but did not inhibit the footpad edema induced with a mixture of carrageenin and forskolin. An antihistamine, cyproheptadine, had no effect on carrageenin-induced footpad edema either in the presence or absence of forskolin. These results suggest that both bradykinin and prostaglandins are essential for the development of carrageenin-induced footpad edema and that bradykinin plays an important role in the potentiative effect of forskolin on footpad edema induced with carrageenin in rats.
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PMID:Effect of forskolin on alterations of vascular permeability induced with bradykinin, prostaglandin E1, adenosine, histamine and carrageenin in rats. 668 50

Fast atom bombardment (FAB) mass spectrometry was employed to identify and quantitate dansyl amino acids obtained in the N-terminal analysis of proteins. FAB mass spectra of dansyl amino acids are characterized by intense quasimolecular ions formed by cationization of the molecular species and fragment ions produced by cleavage of the bonds on either side of the sulfanyl group. Investigation of the dansyl amino acid responses using dansyl aminobutyric acid as an internal standard showed that dansyl amino acids can be determined quantitatively at a level of 0.1 nmol. N-terminal residue analysis was performed on a number of proteins to substantiate the technique including bovine serum albumin, pepsinogen, trypsinogen, bromelain, ribonuclease A, and bacteriophage P-22 tail protein.
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PMID:Protein N-terminal analysis using fast atom bombardment mass spectrometry. 686 20

The three tryptic glycopeptides of cationic peanut peroxidase (C. PRX) and the sole one of anionic peanut peroxidase (A. PRX) were individually coupled to bovine serum albumin to raise antisera. The three categories of antibodies directed towards three N-glycans of C. PRX (anti-GLa, anti-GLb and anti-GLc) were isolated from antisera with glycan-conjugated ECH Sepharose 4B affinity columns and the distribution of epitopes on the N-glycans was investigated. The reactivity of anti-GLa, anti-GLb and anti-GLc is inhibited 25-40% by 1 M fucose, compared with a slight inhibition by N-acetylglycosamine and xylose. Mannose and galactose showed no inhibition to anti-GLa and only a slight inhibition to anti-GLb and anti-GLc. All of anti-GLa, anti-GLb and anti-GLc recognize A. PRX and horseradish peroxidase but do not recognize fetuin. Also, their reactivity is inhibited by bromelain by more than 70%. The three categories of antibodies present high homogeneity and appear to be directed mainly towards the core structure [Xyl] (Man)3 [Fuc] (GlcNAc)2. An effective and simple method to screen antibodies with carbohydrate specificities is described herein.
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PMID:Immunogenicity of the N-glycans of peanut peroxidase. 752 14

NZB is a mouse strain that spontaneously develops autoimmune haemolytic anaemia at 10-12 months of age. We analysed the autoantibodies present throughout their life and compared them to natural autoantibodies found in the normal mouse. Sera and Coombs' antibodies eluted from red blood cells (RBC) were tested for their activities against RBC and a panel of antigens: actin, myoglobin, myosin, tubulin, spectrin, DNA and trinitrophenyl bovine serum albumin (TNP-BSA), F(ab')2 and Fc fragments of IgG by using enzyme immunoassays (EIA) and Western blotting analysis of RBC membrane extracts. In NZB mouse sera, activities of IgM and IgG against the whole panel, compared to those of sera from age-matched BALB/c mice, increased progressively throughout life with oscillating values in parallel with the anti-RBC activity. Two periods of autoantibody production seem to exist: the first is characterized by a fluctuating high level of IgM and stable level of IgG natural autoantibodies, and the second by a rise of IgG natural autoantibodies in parallel with IgG anti-RBC antibodies. The presence of idiotype D23 (IdD23), which is characteristic of natural polyspecific autoantibodies, was high on serum IgM and low on IgG autoantibodies throughout life. To further analyse autoantibody level oscillations, we tested IgM and IgG fractions after their separation from whole serum and observed highly enhanced autoantibody activities of both IgM and IgG. These autoreactivities markedly diminished when the separated IgM and IgG fractions were recombined, suggesting humoral control of the autoreactivity as we had already noted for IgG in normal animals. During the first period of autoantibody production, IgM and IgG antibodies eluted from RBC (Combs' antibodies) and those eluted from serum using an RBC-immunoadsorbent (circulating antibodies) reacted with all RBC membrane components, with all antigens of the panel and with F(ab')2 and Fc. Some of these reactivities were comparable to those exhibited by a monoclonal antibody recognizing bromelain-treated RBC. In the second period, both IgM and IgG Coombs' antibodies reacted more strongly with spectrin, and exhibited new specificities, for example against the band 3 polypeptide. IdD23 was abundant on Combs' IgG antibodies in the second period. Taken together, these data suggest that IgM and IgG natural autoantibodies, able to recognize not only RBC antigens but also other antigens, particularly F(ab')2 and Fc fragment of IgG, predominate in Coomb's antibody population.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Natural autoantibodies are involved in the haemolytic anaemia of NZB mice. 798 Aug 46

We investigated whether autoimmune disregulation underlies the formerly reported induction of IgM hypergammaglobulinemia and lymphoid organ enlargement by hexachlorobenzene (HCB) in rats. To this end blood, liver, and lymphoid organs were collected from male Wistar rats after feeding a semisynthetic diet containing 0, 500, or 1000 mg HCB/kg for 3 weeks. Sera prepared from the blood were analyzed for total and (auto)antigen-specific antibody levels by ELISA, organs were weighed, and spleens were further investigated morphologically using immunohistochemically stained cryosections. Present experiments confirmed the ability of HCB to increase total IgM, but not IgG, levels and to increase relative spleen, lymph node, and liver weights. HCB treatment elevated IgM, but not IgG, levels against single-stranded DNA, native DNA, rat IgG (representing rheumatoid factor), and bromelain-treated mouse erythrocytes that expose phosphatidylcholine as a major autoantigen. Antibody levels against the foreign antigens sheep erythrocytes, tetanus toxoid, and bovine serum albumin remained unaffected. The IgM autoantibodies proved to be polyreactive. Morphometric analysis of spleen sections showed that HCB caused a proportionally equal expansion of all splenic compartments, but when individual spleen weights were taken into account a significantly larger expansion of the predominantly B cell-containing marginal zones could be noted. The latter compartment also contained an increased number of macrophages that can be recognized by the monoclonal antibody ED3. The ability of HCB to elevate serum antibody levels against autoantigens, but not foreign antigens, indicates that HCB probably does not act by polyclonal B cell activation. The IgM isotype, the repertoire, and the polyreactivity of the serum autoantibodies suggest that HCB activates a recently described B cell subset shown to be committed to the production of these autoantibodies and associated with various systemic autoimmune diseases. Since the marginal zone is considered to be the splenic lodging site of this B cell subset and since increases of ED3+ macrophages have been associated with autoimmune diseases in the rat, the observed changes of the marginal zones in HCB-treated rats is in line with this notion.
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PMID:Autoimmune effects of hexachlorobenzene in the rat. 821 5

Carbohydrates have been suggested to account for some IgE cross-reactions between various plant, insect, and mollusk extracts, while some IgG antibodies have been successfully raised against plant glycoproteins. A rat monoclonal antibody raised against elderberry abscission tissue (YZ1/2.23) and rabbit polyclonal antiserum against horseradish peroxidase were screened for reactivity in enzyme-linked immunosorbent assay against a range of plant glycoproteins and extracts as well as neoglycoproteins, bee venom phospholipase, and several animal glycoproteins. Of the oligosaccharides tested, Man3XylFucGlcNAc2(MMXF3) derived from horseradish peroxidase was the most potent inhibitor of the reactivity of both YZ1/2.23 and anti-horseradish peroxidase to native horseradish peroxidase glycoprotein. The reactivity of YZ1/2. 23 and anti-horseradish peroxidase against Sophora japonica lectin was most inhibited by a neoglycoconjugate of bromelain glycopeptide cross-linked to bovine serum albumin, while the defucosylated form of this conjugate was inactive as an inhibitor. A wide range of plant extracts was found to react against YZ1/2.23 and anti-horseradish peroxidase, with particularly high reactivities recorded for grass pollen and nut extracts. All these reactivities were inhibitable with the bromelain glycopeptide/bovine serum albumin conjugate. Bee venom phospholipase and whole bee venom reacted weakly with YZ1/2.23 but more strongly with anti-horseradish peroxidase in a manner inhibitable with the bromelain glycopeptide/bovine serum albumin conjugate, while hemocyanin from Helix pomatia reacted poorly with YZ1/2.23 but did react with anti-horseradish peroxidase. It is concluded that the alpha1, 3-fucose residue linked to the chitobiose core of plant glycoproteins is the most important residue in the epitope recognized by the two antibodies studied, but that the polyclonal anti-horseradish peroxidase antiserum also contains antibody populations that recognize the xylose linked to the core mannose of many plant and gastropod N-linked oligosaccharides.
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PMID:Core alpha1,3-fucose is a key part of the epitope recognized by antibodies reacting against plant N-linked oligosaccharides and is present in a wide variety of plant extracts. 962 Nov 6

In patients with chronic renal failure, cancer incidence is enhanced. Since levels of advanced glycation end products (AGEs) are markedly elevated in renal insufficiency, we investigated potential effects of various AGEs on structural DNA integrity in tubule cells. The comet-assay was employed, a method based on the computer-aided microscopic analysis of single cells after electrophoretic separation of their nuclear DNA. Incubation of pig kidney LLC-PK1-cells for 24 h with AGE-BSA (AGE-bovine serum albumin), carboxymethyllysine-BSA as well as methylglyoxal-BSA resulted in a significant increase in DNA damage. Pretreatment of the cells with the proteases trypsin and bromelain abolished the AGE-induced comet-formation. This is in agreement with the idea that the observed genotoxicity of AGEs could be receptor-mediated and that proteases inactivate the extracellular domain of the receptor for AGEs. Binding of AGEs to the RAGE receptor leads to an increased intracellular formation of active oxygen species, which are known to induce DNA damage. It is concluded that AGEs induce genotoxicity in tubule cells, which may be involved in the enhanced cancer development in advanced kidney diseases.
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PMID:Genotoxicity of advanced glycation end products in mammalian cells. 1256 69


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