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

Papain [EC 3.4.22.2] was photooxidized using methylene blue as a sensitizer. The photooxidzed enzyme lost its caseinolytic activity and had significantly decreased histidine and tryptophan contents. The tyrosine content was the same before and after the photooxidation. The SH content of the photooxidized enzyme, as determined after reduction with dithiothreitol, was also unchanged. The loss of histidine was always slower than the loss of enzymatic activity, being less than one residue per molecule even when the enzymatic activity was completely lost. However, the inactivation and the oxidation of a histidine residue were pH-dependent in a similar fashion in the pH range of 5.0-8.0, the pH profiles conforming to theoretical titration curves with apparent pKa values of 6.6 and 6.7, respectively. The fact that the ionization of a histidine residue in papain has a normal imidazole pKa value is entirely in accord with the finding for stem bromelain [EC 3.4.22.4] (Murachi, T., Tsudzuki, T., & Okumura, K. (1975) Biochemistry 14, 249-255), and is of great significance in relation to the mechanism of catalysis by these enzymes.
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PMID:Photooxidation of histidine and tryptophan residues of papain in the presence of methylene blue. 23 35

Red cells were pretreated with the proteolytic enzymes bromelain or papain prior to use in antibody-dependent cell-mediated cytotoxicity (ADCC) assays with lymphocytes or peripheral blood mononuclear cells (PBMC) as effector cells. At low concentrations of anti-D or anti-A, lysis of papain-treated cells by lymphocytes was greater than that of bromelain-treated cells. Papain digestion resulted in both greater sensitivity to haemolysis by lymphocytes or PBMC and higher agglutination titres of anti-D-sensitised red cells than bromelain. With anti-A, however, although papain also promoted greater haemolysis, it was slightly less effective at red cell agglutination than bromelain.
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PMID:Comparison of lysis of bromelain and papain treated red cells in ADCC assays. 154 38

Peptide synthesis catalysed by papain was studied using thio-alpha-amino acids (S-acids) as a carboxyl component. It was found, for example, that with Z-AlaSH (pK 2.70) the maximal yield of the peptide Z-AlaValNH2 was obtained at pH 8-8.5. A two-fold excess of Z-AlaSH furnished peptides with yields close to 100%. Thio-amino acids with bulky side groups, for example, Z-IleSH, Z-Asp(OBu')SH, gave peptides with a low yield. Papain interacts with Z-AlaSH better than do bromelain or ficin.
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PMID:Thio-alpha-amino acids (S-acids) as a carboxyl component in peptide synthesis catalysed by papain. 234 57

Radioimmunoassays (RIA) have confirmed previous studies that trimethylammonium (TMA) or its derivatives constitute part of the determinant recognized by naturally-occurring antibodies (NOA) with the ability to interact with bromelain-treated mouse erythrocytes (BrMRBC). Further studies on this determinant revealed its presence on erythrocytes from several species in addition to mice. In most cases (except in chickens) the determinant was cryptic and could be exposed only after proteolytic treatment of the erythrocytes. The determinant was also found on certain murine lymphoma cells. We also found that bromelain was not the only enzyme that could be used to expose the determinant. Papain, but not trypsin, was able to unmask the determinant on mouse erythrocytes. Rabbit antibodies directed against the idiotypes of four different monoclonal BrMRBC-binding NOA were prepared. Direct RIA assays and inhibition assays showed that the different monoclonal BrMRBC-binding NOA shared a common idiotype specific to such antibodies. The common idiotype was detected in the serum from several mouse strains and in wild mice.
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PMID:Further studies on the determinant recognized by naturally-occurring murine autoantibodies reacting with bromelain-treated erythrocytes. 245 52

Two types of proteinase inhibitors were purified from Enterolobium contortisiliquum beans. The inhibitor of serine-proteinases inhibited trypsin (Ki = 5 nM), chymotrypsin (Ki = 10 nM) and plasma kallikrein, but not tissue kallikreins. The molecular weight is approximately 23 kDal and two polypeptide chains are detected after reduction. The second inhibitor with activity directed against SH-proteinases was isolated by CM-papain-Sepharose. The molecular weight is approximately 60 kDal and only one polypeptide chain was detected after reduction. Papain (Ki = 0.6 nM) and bromelain are inhibited.
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PMID:Serine- and SH-proteinase inhibitors from Enterolobium contortisiliquum beans. Purification and preliminary characterization. 348 36

The thiol protease, bromelain, an extract from pineapple stem, was suggested to have antithrombotic and anticoagulant activities in vivo. We studied the effects of bromelain on cell size distribution of isolated human platelets in vitro by Coulter Counter measurements. Preincubation of platelets with bromelain (10 micrograms/mL) completely prevented the thrombin (0.2 U/mL) induced platelet aggregation. Papain was less active in preventing platelet aggregation. In vitro, bromelain (0.1 microgram/mL) reduced the adhesion of bound, thrombin stimulated, fluorescent labeled platelets to bovine aorta endothelial cells. In addition, preincubation of platelets with bromelain, prior to thrombin, activation, reduced the platelet adhesion to the endothelial cells to the low binding value of unstimulated platelets. On the basis of mass concentrations, the proteases papain and trypsin were as effective as bromelain. Using a laser thrombosis model, the in vivo effects of orally and intraveneously applied bromelain on thrombus formation in rat mesenteric vessels were studied. Bromelain, orally applied at 60 mg/kg body weight, inhibited the thrombus formation in a time dependent manner, the maximum being after 2 hours in 11% of arterioles and 6% of venoles. Intravenous application at 30 mg/kg was slightly more active in reducing thrombus formation in arterioles (13%) and venoles (5%), suggesting that orally applied bromelain is biologically active. These results may help to explain some of the clinical effects observed after bromelain treatment in patients with thrombosis and related diseases.
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PMID:Bromelain proteases reduce human platelet aggregation in vitro, adhesion to bovine endothelial cells and thrombus formation in rat vessels in vivo. 1021 25

Protease-catalyzed polymerization and copolymerization of L-glutamic acid diethyl ester hydrochloride (1) have been performed in a buffer of high concentration. Papain and bromelain showed high catalytic activity toward the polymerization. H-H COSY NMR analysis of the product showed the exclusive formation of poly(alpha-peptide), which was further confirmed by comparison with NMR spectra of poly(alpha-methyl gamma-L-glutamate). The papain-catalyzed polymerization of gamma-methyl L-glutamate did not occur under the similar reaction conditions, supporting the regioselective production of the polymer having an alpha-peptide linkage from 1. The effects of the reaction parameters have been systematically investigated. The copolymerization of 1 with various amino acid esters took place by the papain catalyst to give peptide copolymers.
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PMID:Protease-catalyzed regioselective polymerization and copolymerization of glutamic acid diethyl ester. 1188 18

A chemoenzymatic syntheses was developed for new highly specific fluorogenic substrates for cysteine proteases of the papain family, Abz-Phe-Ala-pNA (I) and Glp-Phe-Ala-Amc (II) (Abz, pNA, Glp, and Amc are i-aminobenzoyl, p-nitroanilide, pyroglutamyl, and 4-amino-7-methylcoumaride, respectively). Substrate (I) was obtained in an aqueous-organic medium using native chymotrypsin. Substrate (II) was synthesized in DMF-MeCN by the treatment with chymotrypsin and subtilisin Carlsberg immobilized on polyvinyl alcohol cryogel. Hydrolysis of substrate (I) with papain, ficin, and bromelain was accompanied by a 15-fold increase in fluorescence intensity, and that of substrate (II), by a change in the fluorescence spectrum. Unambiguity of enzymatic hydrolysis of the substrates after the Ala residue was shown. The specific activity of the substrate hydrolysis with papain, bromelain, and ficin and was determined. Papain showed the greatest activity for both substrates. The activity of all proteases under study was essentially higher for substrate (II), than for substrate (I). The lowest detectable papain concentrations were 2.4 x 10(-10) M for (I) and 1.2 x 10(-11) M for (II). A high selectivity of cysteine proteases for Glp-Phe-Ala-Amc was established.
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PMID:[Chemoenzymatic synthesis of new fluorogenous substrates for cysteine proteases of the papain family]. 1867 88

Proteases, lipase, and chitinase killed Tylenchorhynchus dubius in vitro and in soil. Tylenchorhynchus dubius was more susceptible to the enzymes than Pratylenchus penetrans. Papain was the most effective protease, and other enzymes were less effective. Heating enzymes to 80 C for 10 min greatly reduced nematicidal effectiveness. Scanning electron micrographs showed that papain and chitinase produced structural changes in the cuticle of T. dubius. Lipase removed a thin outer layer. Papain removed material filling the striata, or furrow, between the horizontal bands. When added to soil, chitinase, lipase, collagenase, and proteases (papain and bromelain) decreased motility of T. dubius populations up to 75%. Bromelain was the most active in soil against T. dubius, and collagenase was the most active in soil against P. penetrans.
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PMID:Effects of hydroclytic enzymes on plant-parasitic nematodes. 1930 92

The thiolprotease bromelain, isolated from pine apple stem, was suggested for use in adjuvant tumor therapy. This study examined the in vitro effects of crude bromelain, bromelain F9 and papain on B16F10 mouse melanoma cell lung colonization, in vitro cell proliferation, invasion through matrigel and CD44 expression. In vitro treatment of the melanoma cells with bromelain F9 and papain before i.v. injection into mice prevented lung colonization. The lung weight at day 20 was significantly reduced from 5.1% (untreated cells) to 1.6% (bromelain F9 treated cells). Papain was as effective as bromelain F9. However, there was no difference in the lung weight between bromelain F9 treated and the untreated group at day 27. Protease removal and further incubation of the B16F10 cells retained their capacity to induce lung tumor metastases. The proteases inhibited growth of the melanoma cells in a dose dependent manner. Crude bromelain was most active with a half maximal value of 7.5 mu g/ml. However, the antiproliferative effects did not correlate with the proteolytic activity. In a matrigel invasion assay, the proteases reduced the invasive capacity of the melanoma cells maximally by about 30%. Using flow cytometry, the proteases were found to reduce the CD44 density, present on the melanoma cells, to a different degree: crude bromelain was more active than bromelain F9 and papain, which had higher proteolytic activity. Crude bromelain was most active in abolishing the CD44 re-expression after protease treatment.
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PMID:Bromelain proteases suppress growth, invasion and lung metastasis of B16F10 mouse melanoma cells. 2152 6


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