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)

Treatment of T cells with the cysteine protease bromelain has been widely used to enhance the binding of human T cells to human E (autologous E rosettes) and has been shown to remove surface T cell CD44 molecules. Ligand binding to CD44 has been shown to markedly augment T cell activation. To study the activation potential of bromelain-treated CD44 T cells, we have compared the proliferation of sham- and bromelain-treated normal human PBMC to mitogenic CD2 mAb. We found that bromelain not only removed T cell CD44, but also removed the CD45RA isoform of CD45 as well as E2/MIC2, CD6, CD7, CD8, and Leu 8/LAM1 molecules. T cell proliferation in response to CD2 mAb was increased 325% in bromelain-treated PBMC compared to sham-treated PBMC (p < 0.005). Reciprocal treatment experiments using purified T cells and monocytes demonstrated that the enhancement of T cell CD2 activation by bromelain occurred only when T cells were treated with bromelain and was accompanied by increased adhesion of T cells to monocytes. These data demonstrate that expression of portions of the extracellular domains of the CD44, CD45RA, E2/MIC2, CD6, CD7, CD8, and Leu 8/LAM1 surface molecules are not required for CD2 activation of human T cells. Rather, the removal of these surface molecules by bromelain is associated with enhanced T cell-monocyte aggregation and enhanced CD2-mediated T cell activation. Taken together with data that CD44, E2/MIC2, CD6, and CD7 mAb inhibit CD2/lymphocyte function-associated Ag-3-mediated cellular interactions and also augment CD2-mediated triggering of T cells, these data suggest that members of the bromelain-sensitive group of surface molecules may comprise a set of CD2-associated adhesion ligands that acts in concert to modulate human T cell activation.
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PMID:Bromelain treatment of human T cells removes CD44, CD45RA, E2/MIC2, CD6, CD7, CD8, and Leu 8/LAM1 surface molecules and markedly enhances CD2-mediated T cell activation. 128 Nov 88

Cysteine protease inhibitors that specifically reacted with several cysteine proteases were found in KSCN extract of human melanoma tissue. From 30 gm of the tissue, approximately 593.5 U inhibitor was obtained. The inhibitors were adsorbed on a papain-Sepharose column and could be eluted with 10 mmol/L phosphate buffer, pH 6.0, containing NaCl or KCl, or with 20 mmol/L acetate buffer, pH 4.0, containing KSCN. They revealed a strong inhibitory activity for cysteine proteases such as ficin, papain, and cathepsin B, but did not react with cysteine protease bromelain or serine protease trypsin. No immunologic relationship was confirmed between the inhibitor and other well-known plasma inhibitors such as alpha 1-antitrypsin, alpha 2-macroglobulin, alpha 1-antichymotrypsin, antithrombin III, C1-in-activator, and alpha 2-plasmin inhibitor. With Sephadex G-100, two main peaks of molecular weight 40,000 and 10,000 were detected in the KSCN extract of the human melanoma tissue. However, the inhibitors revealed three molecular weights of 10,000, 25,000, and 80,000 when estimated by Sephadex G-100 gel filtration after papain-Sepharose affinity chromatography. On the other hand, the molecular weights of the inhibitors changed to two peaks of 25,000 and 10,000 on rechromatography with a papain-Sepharose column.
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PMID:Cysteine protease inhibitors isolated from human malignant melanoma tissue. 393 99

One of the bromelain inhibitors, isoinhibitor VI (BI-VI), was purified from pineapple stem powder and its complete amino acid sequence was determined by conventional protein sequencing. These results revealed that the protein consists of an 11-residue light chain and a 41-residue heavy chain, cross-linked to each other by disulfide bonds to form the native inhibitor of 52 residues (M(r) = 5888). The secondary structure of BI-VI was analyzed based on the sequence-specific 1H resonance assignment of its two-dimensional NMR spectra. BI-VI was shown to be composed of two domains (A and B) which are formed by antiparallel beta-sheets, but has no alpha-helix. These results were consistent with the CD spectra of BI-VI. Residues Lys27-Ile29 (heavy chain) form a triple-stranded antiparallel beta-sheet with residues Asp9-Tyr11 and Lys22-Glu24 (heavy chain) in the A domain and residues Cys5-Cys7 (heavy chain) form another triple-stranded beta-sheet with residues Cys6-Cys8 (light chain) and Asp32-Ile34 (heavy chain) in the B domain. The secondary structure as well as the primary structure of BI-VI was distinctly different from that of the other cysteine protease inhibitor, cystatin, and from that of basic pancreatic trypsin inhibitor.
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PMID:Primary structure, sequence-specific 1H-NMR assignments and secondary structure in solution of bromelain inhibitor VI from pineapple stem. 755 79

The amino acid sequences of ananain (EC3.4.22.31) and stem bromelain (3.4.22.32), two cysteine proteases from pineapple stem, are similar yet ananain and stem bromelain possess distinct specificities towards synthetic peptide substrates and different reactivities towards the cysteine protease inhibitors E-64 and chicken egg white cystatin. We present here the complete amino acid sequence of ananain and compare it with the reported sequences of pineapple stem bromelain, papain and chymopapain from papaya and actinidin from kiwifruit. Ananain is comprised of 216 residues with a theoretical mass of 23464 Da. This primary structure includes a sequence insert between residues 170 and 174 not present in stem bromelain or papain and a hydrophobic series of amino acids adjacent to His-157. It is possible that these sequence differences contribute to the different substrate and inhibitor specificities exhibited by ananain and stem bromelain.
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PMID:Complete amino acid sequence of ananain and a comparison with stem bromelain and other plant cysteine proteases. 935 53

A cysteine protease, phytolacain R from full-growth greenish fruits of pokeweed, Phytolacca americana L, was purified to electrophoretic homogeneity by a simple purification procedure employing CM-Sepharose ion-exchange chromatography. The enzyme was present in low content in the young fruits about 50 d after flowering but gradually accumulated in growing fruits. Its molecular mass was estimated to be ca. 23 kDa by SDS-PAGE, and its sugar content was zero. Its amino acid sequence was established by automated sequence analysis of the peptides obtained by cleavage with Achromobacter protease I, chymotrypsin, trypsin, and cyanogen bromide. The enzyme is composed of 218 amino acid residues, of which it shares 110 residues (50%) with papain, 104 (47%) with actinidain, and 87 (40%) with stem bromelain. The amino acid residues forming the substrate-binding the S2 pocket of papain, Tyr61, Tyr67, Pro68, Trp69, Val133, and Phe207, were predicted to be replaced by Gly, Trp, Met, His, Ala, and Met in phytolacain R, respectively. As a consequence of these substitutions, the S2 pocket is expected to be less hydrophobic in phytolacain R than in papain.
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PMID:Amino acid sequence and some properties of phytolacain R, a cysteine protease from full-growth fruits of pokeweed, Phytolacca americana. 1039 17

Recently, it has emerged that extracellular proteases have specific regulatory roles in modulating immune responses. Proteases may act as signaling molecules to activate the Raf-1/extracellular regulated kinase (ERK)-2 pathway to participate in mitogenesis, apoptosis, and cytokine production. Most reports on the role of protease-mediated cell signaling, however, focus on their stimulatory effects. In this study, we show for the first time that extracellular proteases may also block signal transduction. We show that bromelain, a mixture of cysteine proteases from pineapple stems, blocks activation of ERK-2 in Th0 cells stimulated via the TCR with anti-CD3epsilon mAb, or stimulated with combined PMA and calcium ionophore. The inhibitory activity of bromelain was dependent on its proteolytic activity, as ERK-2 inhibition was abrogated by E-64, a selective cysteine protease inhibitor. However, inhibitory effects were not caused by nonspecific proteolysis, as the protease trypsin had no effect on ERK activation. Bromelain also inhibited PMA-induced IL-2, IFN-gamma, and IL-4 mRNA accumulation, but had no effect on TCR-induced cytokine mRNA production. This data suggests a critical requirement for ERK-2 in PMA-induced cytokine production, but not TCR-induced cytokine production. Bromelain did not act on ERK-2 directly, as it also inhibited p21ras activation, an effector molecule upstream from ERK-2 in the Raf-1/MEK/ERK-2 kinase signaling cascade. The results indicate that bromelain is a novel inhibitor of T cell signal transduction and suggests a novel role for extracellular proteases as inhibitors of intracellular signal transduction pathways.
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PMID:Bromelain, from pineapple stems, proteolytically blocks activation of extracellular regulated kinase-2 in T cells. 1045 95

Many plants contain latex that exudes when leaves are damaged, and a number of proteins and enzymes have been found in it. The roles of those latex proteins and enzymes are as yet poorly understood. We found that papain, a cysteine protease in latex of the Papaya tree (Carica papaya, Caricaceae), is a crucial factor in the defense of the papaya tree against lepidopteran larvae such as oligophagous Samia ricini (Saturniidae) and two notorious polyphagous pests, Mamestra brassicae (Noctuidae) and Spodoptera litura (Noctuidae). Leaves of a number of laticiferous plants, including papaya and a wild fig, Ficus virgata (Moraceae), showed strong toxicity and growth inhibition against lepidopteran larvae, though no apparent toxic factors from these species have been reported. When the latex was washed off, the leaves of these lactiferous plants lost toxicity. Latexes of both papaya and the wild fig were rich in cysteine-protease activity. E-64, a cysteine protease-specific inhibitor, completely deprived the leaves of toxicity when painted on the surface of papaya and fig leaves. Cysteine proteases, such as papain, ficin, and bromelain, all showed toxicity. The results suggest that plant latex and the proteins in it, cysteine proteases in particular, provide plants with a general defense mechanism against herbivorous insects.
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PMID:Papain protects papaya trees from herbivorous insects: role of cysteine proteases in latex. 1473 Dec 57

Proteases regulate numerous biological processes with a degree of specificity often dictated by the amino acid sequence of the substrate cleavage site. To map protease/substrate interactions, a 722-member library of fluorogenic protease substrates of the general format Ac-Ala-X-X-(Arg/Lys)-coumarin was synthesized (X=all natural amino acids except cysteine) and microarrayed with fluorescent calibration standards in glycerol nanodroplets on glass slides. Specificities of 13 serine proteases (activated protein C, plasma kallikrein, factor VIIa, factor IXabeta, factor XIa and factor alpha XIIa, activated complement C1s, C1r, and D, tryptase, trypsin, subtilisin Carlsberg, and cathepsin G) and 11 papain-like cysteine proteases (cathepsin B, H, K, L, S, and V, rhodesain, papain, chymopapain, ficin, and stem bromelain) were obtained from 103,968 separate microarray fluorogenic reactions (722 substrates x 24 different proteases x 6 replicates). This is the first comprehensive study to report the substrate specificity of rhodesain, a papain-like cysteine protease expressed by Trypanasoma brucei rhodesiense, a parasitic protozoa responsible for causing sleeping sickness. Rhodesain displayed a strong P2 preference for Leu, Val, Phe, and Tyr in both the P1=Lys and Arg libraries. Solution-phase microarrays facilitate protease/substrate specificity profiling in a rapid manner with minimal peptide library or enzyme usage.
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PMID:High throughput substrate specificity profiling of serine and cysteine proteases using solution-phase fluorogenic peptide microarrays. 1570 70

A unique 33-kDa cysteine protease (Mir1-CP) rapidly accumulates at the feeding site in the whorls of maize (Zea mays L.) lines that are resistant to herbivory by Spodoptera frugiperda and other lepidopteran species. When larvae were reared on resistant plants, larval growth was reduced due to impaired nutrient utilization. Scanning electron microscopy (SEM) indicated that the peritrophic matrix (PM) was damaged when larvae fed on resistant plants or transgenic maize callus expressing Mir1-CP. To directly determine the effects of Mir1-CP on the PM in vitro, dissected PMs were treated with purified, recombinant Mir1-CP and the movement of Blue Dextran 2000 across the PM was measured. Mir1-CP completely permeabilized the PM and the time required to reach full permeability was inversely proportional to the concentration of Mir1-CP. Inclusion of E64, a specific cysteine protease inhibitor prevented the damage. The lumen side of the PM was more vulnerable to Mir1-CP attack than the epithelial side. Mir1-CP damaged the PM at pH values as high as 8.5 and more actively permeabilized the PM than equivalent concentrations of the cysteine proteases papain, bromelain and ficin. The effect of Mir1-CP on the PMs of Helicoverpa zea, Danaus plexippus, Ostrinia nubilalis, Periplaneta americana and Tenebrio molitor also was tested, but the greatest effect was on the S. frugiperda PM. These results demonstrate that the insect-inducible Mir1-CP directly damages the PM in vitro and is critical to insect defense in maize.
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PMID:Degradation of the S. frugiperda peritrophic matrix by an inducible maize cysteine protease. 1624 50

The present work reports the characterization of Fastuosain, a novel cysteine protease of 25kDa, purified from the unripe fruits of Bromelia fastuosa, a wild South American Bromeliaceae. Proteolytic activity, measured using casein and synthetic substrates, was dependent on the presence of thiol reagents, having maximum activity at pH 7.0. The present work reports cDNA cloning of Fastuosain; cDNA was amplified by PCR using specific primers. The product was 1096pb long. Mature fastuosain has 217 residues, and with the proregion has a total length of 324 residues. Its primary sequence showed high homology with ananain(74%), stem bromelain (66%) and papain (44%).
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PMID:Preliminary functional characterization, cloning and primary sequence of Fastuosain, a cysteine peptidase isolated from fruits of Bromelia fastuosa. 1645 75


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