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)

Incubation of guinea pig lung mitochondrial suspension in an isotonic low ionic strength buffer containing various proteolytic enzymes caused significant stimulation of the glycerophosphate acyltransferase activity. The maximal stimulation range between 20 and 105%, and the order was as follows: bromelain greater than chymotrypsin greater than pronase greater than trypsin greater than papain greater than nagarse. Under hypotonic conditions, over 85% of GAT was destroyed by all the proteolytic enzymes. Microsomal enzyme activity was consistently inhibited (greater than 95%) by exposure to any of these proteases even under isotonic conditions. These results suggest that GAT is located on the inner aspect of the mitochondrial outer membrane. Also, it is likely that a portion of this enzyme or that of a modulator is present in the outer side of the outer membrane and proteolysis of this component causes stimulation.
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PMID:Location of glycerol phosphate acyltransferase in the transverse plane of mitochondrial outer membrane of guinea pig lung. 638 69

L-Pyroglutamyl-L-phenylalanyl-L-leucine-p-nitroanilide (PFLNA)--a convenient chromogenic substrate for assay of thiol proteinases papain, ficin, and bromelain--was prepared by enzymatic synthesis with chymotrypsin as a catalyst. The thiol proteinases hydrolyze PFLNA with the liberation of p-nitroaniline, estimated spectrophotometrically by its absorbance at 410 nm. The phenylalanine residue in the P2 position of PFLNA meets the specificity demands of thiol proteinases. The following values of Km were found for PFLNA hydrolysis: by papain, 0.34 mM; by ficin, 0.43 mM; by bromelain, 0.30 mM. This substrate was successfully applied to monitor thiol proteinase affinity chromatography on bacitracin-Sepharose, which resulted in a 2- to 4-fold purification from commercial preparations.
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PMID:L-Pyroglutamyl-L-phenylalanyl-L-leucine-p-nitroanilide--a chromogenic substrate for thiol proteinase assay. 639 97

Agglutinability of red blood cells against anti-D increased remarkably when the cells were treated with proteolytic enzymes, such as bromelain, chymotrypsin, ficin, papain, pronase and trypsin. When stroma prepared from normal red blood cells was treated with any of proteolytic enzymes, however, Rh-Hr blood type activities were completely abolished. The similar results were obtained from stroma solubilized with detergents which was treated with enzymes after being prepared. Of all the enzymes, ficin acted more slowly than the others did. Neuraminidase or phospholipase A2 had no effect on Rh-Hr activities at all. SDS-polyacrylamide gel electrophoretic pattern of stroma prepared from bromelain, ficin and pronase-treated red blood cells were quite different from that of normal stroma.
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PMID:Rh0(D) activity of red blood cells and stroma treated with proteolytic enzymes. 643 38

Development of mitochondrial and microsomal glycerophosphate acyltransferase in the fetal guinea pig lung was investigated. Mitochondrial and microsomal enzyme activity gradually increased from 45 days to 55 days of gestation. The specific activity in the microsomal fraction (8.2 nmol/min per mg protein) then declined until term, but increased again in the 24-h newborn from 2.5 to 6.1 nmol/min per mg protein. Glycerophosphate acyltransferase activity in the mitochondrial fraction declined after 55 days (3.5 nmol/min per mg) to a minimum level at 60 days (1.8 nmol/min per mg), but increased again in the 24-h newborn (4.0 nmol/min per mg). The specific activity of both mitochondrial and microsomal enzyme declined after 24 h after birth until adult levels were attained. Glycerophosphate acyltransferase activity in mitochondria and microsomes from adult lung was 0.8 and 2.0 nmol/min per mg, respectively. Microsomal enzyme activity was consistently inhibited (over 95%) throughout gestation and adulthood by exposure to any one of several proteinases: trypsin, chymotrypsin, papain, bromelain, pronase and nagarse. Although mitochondrial enzyme activity was also inhibited by these proteinases, there was a continuous increase in proteinase-resistant glycerophosphate acyltransferase activity between 45 days of gestation and term. In contrast, adult mitochondrial enzyme activity was stimulated by all the proteinases studied. These results suggest that early in gestation, glycerophosphate acyltransferase lies more exposed on the cytoplasmic side of the mitochondrial outer membrane and as gestation progresses it becomes embedded into the phospholipid bilayer.
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PMID:Development of glycerophosphate acyltransferase in guinea pig lung mitochondria and microsomes. 643 51

L-selectin, the peripheral lymph node "homing receptor," is an adhesion protein that mediates lymphocyte binding to lymph node high endothelial venules. Ligands for this protein have been identified only on endothelial cells, and recent murine studies indicate that CD34 on endothelial cells is an L-selectin ligand. To investigate whether CD34 expressed on hematopoietic cells functions as an L-selectin ligand, we used an in vitro binding assay to examine lymphocyte adherence to KG1a, a CD34+ human hematopoietic progenitor cell line. We observed specific L-selectin-mediated adherence of lymphocytes to KG1a: the binding was calcium-dependent, was strictly inhibited by anti-L-selectin antibodies and by carbohydrate ligands of L-selectin, and was abrogated by induction of L-selectin shedding from the lymphocyte membrane by treatment with phorbol esters. However, blocking studies using anti-CD34 antibodies, and experiments using KG1a cells sorted for CD34 expression and COS-7 cells transfected with full-length CD34 cDNA indicate that the ligand on KG1a is not CD34; moreover, RPMI 8402, a CD34+ cell line, does not support lymphocyte adherence in the binding assay. Treatment of KG1a with the enzymes neuraminidase, chymotrypsin, and bromelain abrogated lymphocyte binding to the cells, indicating that the ligand is a glycoprotein. These experiments show that CD34 on hematopoietic cells is not an L-selectin ligand and provide the first evidence of a ligand for L-selectin present on a non-endothelial cell.
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PMID:Detection of an L-selectin ligand on a hematopoietic progenitor cell line. 752 35

The ligand-filled 32-kDa fragment of the porcine estradiol receptor extending from His267 to the C-terminal Ile595 was purified to homogeneity by adsorption to mAb 13H2. The native protein was exposed at 4 degrees C to a panel of proteases: thermolysin, subtilisin, pronase, elastase, ficin, bromelain, endopeptidase Lys-C, both in the dimer and the monomer state, and chymotrypsin at pH 8.2 only. The digests were analysed by SDS/PAGE/Western blotting for Coomassie staining and immunostaining. Peptides were sequenced from blots. The majority of cleavage sites in upper domain E (8 out of 11) amassed in the Leu296-Leu310 stretch. Cleavage at Leu319 was seen with subtilisin and at Tyr328 with chymotrypsin. Susceptability to enzymic proteolysis was also pronounced in Thr465-Glu470 at the center of domain E. Three peptides, 13 kDa with thermolysin, beginning at Leu337, 6 kDa and, in low yield, 5 kDa with endopeptidase Lys-C beginning at Asp473 resp. Cys417 were only obtained from the monomer substrate. The various digests featured either 27-23-kDa peptides or mixtures of 17-13-kDa and 12-7-kDa peptides separable by SDS/PAGE. All peptides with N-termini between Leu297 and Ser329 reacted with mAb 13H2. The digests showed high peaks of bound estradiol in the dimer position of 32-kDa fragment controls on density gradient centrifugation at pH 7.4. However, the property of proton-driven dissociation was only preserved in the pronase, elastase and chymotrypsin digests with peptides extending beyond the His547-ArgLeuHis550 motif. The preservation of the estradiol-binding niche in the tightly complexed peptides of domain E was also demonstrated by refilling after steroid removal. The sites exposed to proteolytic enzymes and the epitope for 13H2 attachment are in good agreement with surface probability plots.
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PMID:Surface mapping of the ligand-filled C-terminal half of the porcine estradiol receptor by restricted proteolysis. 763 63

Polymorphonuclear neutrophils (PMN) can be primed for enhanced release of reactive oxygen species (ROS) by exposure to cytokines and biological response modifiers. ROS are considered to possess tumoricidal activity. The polyenzyme preparation Wobenzym (WE) contains pancreatin, papain, bromelain trypsin and chymotrypsin and is used in adjuvant tumor therapy. We investigated killing of WE-exposed PMN against tumor cells and analyzed WE influence on ROS production in a chemiluminescence assay in PMN in vitro and in vivo. Depending on dose WE stimulates the cytotoxic capacity of PMN in vitro against tumor cells (50 micrograms/ml:p < 0.01). Exposure of PMN to Wobenzym caused a time-dependent significant (p < 0.02) increase in release of ROS. Similarly, oral administration of Wobenzym to healthy volunteers (n = 28) resulted in significant increases (p < 0.01) in ROS production, depending on dose (peak with 20 tablets) and time (peak 4 hours after Wobenzym administration). In contrast, ROS production was not elevated in the PMN of healthy volunteers receiving placebo (n = 8) or no treatment (n = 16). These findings point to an immunomodulatory capacity of WE in adjuvant tumor therapy.
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PMID:Stimulation of reactive oxygen species production and cytotoxicity in human neutrophils in vitro and after oral administration of a polyenzyme preparation. 766 74

Protein inhibitors of cysteine proteinases possessing unusual properties have been found in soya (Glycine max) seeds. One of the inhibitor forms has also been detected in Bowman-Birk inhibitor preparations (both commercial and purified by affinity chromatography on chymotrypsin-Sepharose ones). A peculiarity of the inhibitors is that they irreversibly lose their activity in the presence of reducing agents; therefore their effects are normally unobserved under standard conditions of cysteine proteinase inhibitor assays. Soybean inhibitors are represented by two forms with pI of 5.9 and 3.2. The molecular mass of the inhibitor whose pI is equal to 5.8 is about 14 kDa. Both inhibitors suppress the activity of papain, ficin and bromelain.
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PMID:[Cysteine proteinase inhibitors from soy seeds]. 769 28

Pigeon-pea seed extracts have been analyzed for the protease inhibitors using a new, sensitive and simple method for visualization of electrophoretically separated protease inhibitors. The visualization involves equilibrating the gel successively in the protease assay buffer, protease solution, rinsing the gel in protease assay buffer, and exposing it to an exposed, undeveloped X-ray film. Gelatin on the film in places corresponding to the inhibitor bands remains unhydrolyzed. By this method the pigeon-pea seed extract was found to contain nine trypsin and at least seven chymotrypsin inhibitors but no papain or bromelain inhibitors.
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PMID:Detection of electrophoretically separated protease inhibitors using X-ray film. 806 16

A fully active form of hydroxylamine oxidoreductase from Nitrosomonas has been purified with high recovery and shown by reverse-phase high performance liquid chromatography and N-terminal analysis to contain only a 63-kDa subunit and to lack the 11-kDa protein previously thought to be a second subunit. Based on the previously published values of molecular weight in solution, hydroxylamine oxidoreductase probably has an alpha 2 or alpha 3 oligomeric structure. The enzyme was digested separately with trypsin and chymotrypsin and peptides which contained covalently bound heme were separated by high performance liquid chromatography and their amino acid sequences determined. A total of seven heme-containing peptides of unique amino acid sequence were obtained. Six of these heme-containing peptides clearly contained a single c-heme with optical properties indistinguishable from the tryptic heme-containing peptide from horse heart cytochrome c. No noncovalently bound heme was observed. One of the seven heme-containing peptides (T7) was unusual in that it released 2 amino acid residues after each cycle of the Edman degradation due to a nondisulfide cross-link and exhibited a Soret band that was broadened in both the ferric form at neutral pH and the pyridine ferrohemochrome. Subdigestion of peptide T7 with nonspecific proteases (Pronase, bromelain, or pepsin) resulted in the isolation of two smaller heme-containing peptides of unique sequences. One of these was spectrally identical to the other c-heme containing peptides, whereas the second was still apparently cross-linked, again releasing 2 amino acid residues after each Edman cycle. This second peptide possessed a heme-like chromophore with absorption bands (Soret, alpha and beta) red-shifted about 6 nm relative to the spectrum of c-heme-containing peptides. Thus, hydroxylamine oxidoreductase contains a total of eight covalently bound hemes per subunit, seven of which are c-hemes. The eighth, which is attached to a cross-linked peptide, is probably the unusual P460 heme which is unique to hydroxylamine oxidoreductase and thought to be at the active site.
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PMID:Hydroxylamine oxidoreductase from Nitrosomonas europaea is a multimer of an octa-heme subunit. 832 41


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