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)

gamma-Glutamyl transpeptidase is associated with the membranes of a number of epithelial and lymphoid cells. When the enzyme is isolated from rat kidney by a method involving detergent extraction and affinity chromatography, an aggregate of molecular weight greater than 200,000 (heavy form) is obtained. Treatment of the heavy form with bromelain yields a light form of the enzyme (molecular weight of approximately 68,000), which is separable by isoelectric focusing into 12 enzymatically active isozymes which are very similar with respect to catalytic behavior, content of amino acids, hexoses, and aminohexoses, but which differ significantly in sialic acid content. Treatment with neuraminidase converts the acidic isozymes to more basic forms. Each isozyme dissociates in sodium dodecyl sulfate into two nonidentical glycopeptides (molecular weights of 46,000 and 22,000) which can be cross-linked with dimethylsuberimidate to yield a species with an apparent molecular weight of 70,000, which indicates that the isozymes are dimers. Physical and immunological studies indicate that the heavy form of the enzyme contains the dimeric light form as well as other membrane proteins.
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PMID:Subunit structure and isozymic forms of gamma-glutamyl transpeptidase. 0 76

gamma-Glutamyltranspeptidase is associated with the brush border membrane of kidney proximal straight tubule cells. It can be solubilized qualitatively by treatment with papain or Triton X-100. Neither procedure affects its catalytic activity but the two resulting forms of the enzyme differ considerably in their physical properties. The papain-solubilized transpeptidase is soluble in aqueous buffers and was purified 430-fold. It has an s20,w of 4.9 S, a Stokes radius of 36 A, and a calculated molecular weight of 69,000. It appears homogeneous by sedimentation equilibrium centrifugation (Mr=66,700). In contrast, the Triton-solubilized transpeptidase is soluble only in the presence of detergents and was purifed 300-fold. This form of the enzyme has a Stokes radius of 70 A but an s20,w of only 4.15 S. Aggregation of the enzyme just below the critical micelle concentration of Triton X-100 and its ability to bind 1.16 mg of Triton X-100-protein complex was calculated to be 169,000, but the glycoprotein portion of the complex is 52% of the total mass (87,000). The mass of Triton X-100 (82,000) is consistent with its reported micelle molecular weight. Treatment of the Triton-purified transpeptidase with papain or bromelain results in a form of the enzyme identical in all respects with the papain-purified enzyme. Both the Triton- and papain-purified transpeptidase exhibit two protein bands on sodium lauryl sulfate-polyacrylamide gel electrophoresis. The smaller subunits of the two forms appear identical (Mr=27,000), while the larger subunits of the Triton- and papain-purified enzyme have apparent molecular weights of 54,000 and 51,000, respectively. These data suggest that a peptide (3,000 to 19,000) in the larger subunit of gamma-glutamyltranspeptidase is responsible for its binding to Triton micelles and probably for holding the enzyme in the brush border membrane.
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PMID:Comparison of the size and physical properties of gamma-glutamyltranspeptidase purified from rat kidney following solubilization with papain or with Triton X-100. 1 82

Gamma-Glutamyl transpeptidase was purified from rat kidney by a procedure involving Lubrol extraction, acetone precipitation, ammonium sulfate fractionation, treatment with bromelain, and column chromatography on DEAE-cellulose and Sephadex G-100. The final preparation (enzyme III), which exhibits a specific activity about 8-fold higher than that of the purified rat kidney transpeptidase previously obtained in this laboratory (enzyme I), was apparently homogeneous on polyacrylamide gel electrophoresis. Enzyme III is a glycoprotein containing 10% hexose, 7% aminohexose, and 1.5% sialic acid; a tentative molecular weight value of about 70,000 was obtained by gel filtration. Enzyme III has a much lower molecular weight and a different amino acid and carbohydrate content than the less active rat kidney transpeptidase preparation previously obtained, but obtained, but the catalytic properties of these preparations are virtually identical. It is suggested that bromelain treatment may liberate the transpeptidase from a brush border complex that contains other proteins. An improved method is described for the isolation of the higher molecular weight form of the enzyme (enzyme I) in which affinity chromatography on concanavalin A-Sephrose is employed. The purified transpeptidase (enzyme III) is similar to the phosphate-independent maleate-stimulated glutaminase preparation obtained from rat kidney by Katunuma and colleagues with respect to amino acid and carbohydrate content, apparent molecular weight, and relative transpeptidase and maleate-stimulated "glutaminase" activities. Both of these enzyme preparations are much more active in transpeptidation reactions with glutathione and related gamma-glutamyl compounds than with glutamine. In the absence of maleate, the enzyme catalyzes the utilization of glutamine (by conversion to gamma-glutamylglutamine, glutamate, and ammonia) at about 2% of the rate observed for catalysis of transpeptidation between glutathione and glycylglycine; the utilization of glutamine occurs about 8 times more rapidly in the presence of 0.1 M maleate. The transpeptidation and maleate-stimulated glutaminase reactions catalyzed by both enzyme preprations are inhibited by 5 mM L-serine in the presence of 5 mM sodium borate. Studies on gamma-glutamyl transpeptidase and maleate-stimulated glutaminase in the kidneys of fetal rats, newborn rats, and rats after weaning showed parallel development of these activities. The evidence reported here and earlier work in this laboratory strongly support the conclusion that maleate-stimulated glutaminase activity is a catalytic function of gamma-glutamyl transpeptidase. The studies on the ontogeny of gamma-glutamyl transpeptidase and other data are considered in relation to the proposal that this enzyme is involved in amino acid and peptide transport. Its possible role in renal formation of ammonia is also discussed.
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PMID:Identity of maleate-stimulated glutaminase with gamma-glutamyl transpeptidase in rat kidney. 23 5

Isolation and characterization of the platelet aggregation inhibitory factor of bromelain have been presented in this study. Commercial bromelain consists of 3 major components as demonstrated by discontinuous sodium chloride gradient chromatography through carbixymethyl-sephadex column. Fraction I constituted approximately 19% of the total fraction. This fraction had no proteolytic activity or platelet aggregation inhibiting activity, but showed peroxidatic activity. Fraction II and III, which constituted the remainder of the fraction eluted with 135 mM and 800 mM NaCl concentrations, respectively, showed both proteolytic and inhibition of platelet aggregation, but no peroxidatic activity. Immunoelectrophoresis and polyacrylamide electrophoresis showed fraction I with beta-mobility while fraction II and III demonstrated gamma-mobility. It is suggested that the proteolytic activity is associated with the inhibition of platelet aggregation, since oxidation of fractions II and III with sodium tetrathionate abolished both activities. The mechanism of inhibition of platelet aggregation by bromelain is presently unknown but may involve its influence on the prostaglandin synthetic pathway of platelets.
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PMID:Chromatographic fractionation and characterization of the active platelet aggregation inhibitory factor from bromelain. 48 32

Ca(2+)-activated neutral proteinase was purified from rabbit skeletal muscle by a method involving DEAE-Sephacel chromatography, affinity chromatography on organomercurial-Sepharose and gel filtration on Sephacryl S-200 and Sephadex G-150. The SDS (sodium dodecyl sulphate)/polyacrylamide-gel-electrophoresis data show that the purified enzyme contains only one polypeptide chain of mol.wt. 73000. The purification procedure used allowed us to eliminate a contaminant containing two components of mol.wt. about 30000 each. Whole casein or alpha(1)-casein were hydrolysed with a maximum rate at 30 degrees C, pH7.5, and with 5mm-CaCl(2), but myofibrils were found to be a very susceptible substrate for this proteinase. This activity is associated with the destruction of the Z-discs, which is caused by the solubilization of the Z-line proteins. The activity of the proteinase in vitro is not limited to the removal of Z-line. SDS/polyacrylamide-gel electrophoresis on larger plates showed the ability of the proteinase to degrade myofibrils more extensively than previously supposed. This proteolysis resulted in the production of a 30000-dalton component as well as in various other higher- and lower-molecular-weight peptide fragments. Troponin T, troponin I, alpha-tropomyosin, some high-molecular-weight proteins (M protein, heavy chain of myosin) and three unidentified proteins are degraded. Thus the number of proteinase-sensitive regions in the myofibrils is greater than as previously reported by Dayton, Goll, Zeece, Robson & Reville [(1976) Biochemistry15, 2150-2158]. The Ca(2+)-activated neutral proteinase is not a chymotrypsin- or trypsin-like enzyme, but it reacted with all the classic thiol-proteinase inhibitors for cathepsin B, papain, bromelain and ficin. Thus the proteinase was proved to have an essential thiol group. Antipain and leupeptin are also inhibitors of the Ca(2+)-activated neutral proteinase.
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PMID:Purification and some physico-chemical and enzymic properties of a calcium ion-activated neutral proteinase from rabbit skeletal muscle. 53 1

NADPH-cytochrome c reductase, the flavoprotein component of the liver microsomal mixed-function oxidases, has been compared to the corresponding rat lung microsomal enzyme. Both enzymes were purified by the same methods and have identical ionic strength optima towards the reduction of cytochrome c. Antibody directed against the liver reductase identically inhibited the reduction of cytochrome c and ferricyanide by both enzymes. Double diffusion immunoprecipitation on Ouchterlony plates of deoxycholate-solubilized liver and lung microsomes resulted in converging precipitin lines indicating similar antigenic sites. The apparent molecular weights of the detergent-solubilized and bromelain-solubilized lung enzymes were determined by sodium dodecylsulfate-polyacrylamide gel electrophoresis to be 79 000 and 71 000, respectively. From the above criteria we conclude that the enzymes in these two tissues are very similar or identical proteins.
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PMID:Comparative studies of rat liver and lung NADPH-cytochrome c reductase. 80 27

The amino-terminal sequence and composition of the subunits of the hemagglutinin (HA) of influenza virus has been determined. The hemagglutinin has been isolated by two techniques. (1) as the intact hemagglutinin after disruption of the virus in sodium dodecyl sulfate, giving 2 subunits of 58,000 daltons (HA1) and 26,000 daltons (HA2), and (2) after treatment of the virus with bromelain, giving 2 subunits of 58,000 daltons (BHA1) and 21,000 daltons (BHA2). In both preparations these subunits are linked by disulfide bonds. The aminoterminal sequences of HA1 and BHA1, and HA2 and BHA2 are the same. The composition of the 50 residue peptide associated with the membrane, which is removed from the C-terminus of HA2 by bromelain, is deduced and shown to be hydrophobic and contain 50% of the serine residues of HA2. The biosynthetic precursor of the hemagglutinin has been purified from the membranes of abortively infected chick fibroblasts and shown to have the same amino terminus as HA1. Thus the order of biosynthesis is NH2-HA1-HA2-COOH. The amino-terminal sequence of BHA2--at the cleavage site of the precursor--is shown to be a palindrome: NH2-Gly-Leu-Phe-Gly-Ala-Ile-Ala-Gly-Phe-Ile-. This sequence is conserved in representative viruses from each of the major pandemics. A region of homologous sequence is described between the hemagglutinins of influenza type A and B viruses.
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PMID:Studies on the primary structure of the influenza virus hemagglutinin. 105 18

The polypeptide composition of virions of spleen necrosis virus, a reticuloendotheliosis virus, was determined using electrophoresis on sodium dodecyl sulfate-containing, 10 percent polyacrylamide gels. Ten polypeptides were resolved. Four of these were present in minor and somewhat variable amounts. Two proteins, gp71 and gp22, contained D-glucosamine and were located on the outer surface of the lipid envelope, as demonstrated by lactoperoxidase-catalyzed iodination and by bromelain digestion. The results suggest that two of the minor proteins, p36 and p26, were also located on the outer surface, although they lacked D-glucosamine. Treatment of the virus with 0.25 percent Nonidet P-40 and 1 percent dithiothreitol produced a subparticle with a buoyant density of approximately 1.31 g/cm-3. This particle was relatively enriched with polypeptides p77, p62, and p50 and contained small amounts of three other polypeptides.
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PMID:Polypeptide composition of spleen necrosis virus, a reticuloendotheliosis virus. 114 73

A blood coagulation factor, Factor XIII, was highly purified from bovine fresh plasma by a method similar to those used for human plasma Factor XIII. The isolated Factor XIII consisted of two subunit polypeptides, a and b chains, with molecular weights of 79,000 +/- 2,000 and 75,000 +/- 2,000, respectively. In the conversion of Factor XIII to the active enzyme, Factor XIIIa, by bovine thrombin [EC 3.4.21.5], a peptide was liberated. This peptide, designated tentatively as "activation peptide," was isolated by gel-filtration on a Sephadex G-75 column. It contained a total of 37 amino acid residues with a masked N-terminal residue and C-terminal arginine. The whole amino acid sequence of "Activation peptide" was established by the dansyl-Edman method and standard enzymatic techniques, and the masked N-terminal residue was identified as N-acetylserine by using a rat liver acylamino acid-releasing enzyme. This enzyme specifically cleaved the N-acetylserylglutamyl peptide bond serine and the remaining peptide, which was now reactive to 1-dimethylamino-naphthalene-5-sulfonyl chloride. A comparison of the sequences of human and bovine "Activation peptide" revealed five amino acids replacements, Ser-3 to Thr; Gly-5 to Arg; Ile-14 to Val; Thr-18 to Asn, and Pro-26 to Leu. Another difference was the deletion of Leu-34 in the human peptide. Adsorption chromatography on a hydroxylapatite column in the presence of 0.1% sodium dodecyl sulfate was developed as a preparative procedure for the resolution of the two subunit polypeptides, a or a' chain and b chain, constituting the protein molecule of Factor XIII or Factor XIIIa. End group analyses on the isolated pure chains revealed that the structural change of Factor XIII during activation with thrombin occurs only in the N-terminal portion of the a chain, not in the N-terminal end of the b chain or in the C-terminal ends of the a and b chains. From these results, it was concluded that the activation of bovine plasma Factor XIII by thrombin must be accompanied by a limited proteolysis of the arginyl-glycyl bond located in the N-terminal region of the a chain, liberating the "Activation peptide." The possibility of activating Factor XII with other porteinases was examined using Factor Xa [EC 3.4.21.6], Factor XIIa, kallikreins [EC 3.4.21.8], urokinase [EC 3.4.99.26], trypsin [EC 3.4.21.4], ficin [EC 3.4.22.3], papain [EC 3.4.22.2], and bromelain [EC 3.4.22.4]. Among these enzymes, only bromelain and trypsin showed clear activating effects.
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PMID:On the activation of bovine plasma factor XIII. Amino acid sequence of the peptide released by thrombin and the terminal residues of the subunit polypeptides. 122 22

The antiinflammatory, analgesic and antipyretic activities of 3-formylamino-7-methylsulfonylamino-6-phenoxy-4H-1-benzopyran-4-on e (T-614, CAS 123663-49-0) were investigated in various animal models and compared with those of nimesulide, indomethacin and ibuprofen. The antiinflammatory potency of T-614 on carrageenin-induced paw edema, paper disk granuloma and established adjuvant arthritis was greater than that of ibuprofen, but slightly lower than those of nimesulide and indomethacin. In acute inflammatory models, unlike indomethacin, T-614 suppressed the edemas provoked by dextran and bromelain in rats, but its inhibitory action on ultraviolet erythema in guinea-pigs was weak. Although the analgesic activity of T-614 was hardly demonstrated in writhing tests in mice, its potency against the inflammatory pain such as Randall-Selitto test, adjuvant-induced hyperalgesia and antigen-induced arthritic pain in rats was superior to that of ibuprofen. Moreover, it had a potent analgesic effect on urate-induced synovitis in dogs. T-614 exerted a prompt and strong antipyretic effect in both yeast-induced febrile rats and lipopolysaccharide-induced febrile rabbits. T-614 had virtually no gastrointestinal ulcerogenic action and did not affect water and sodium excretion in rats. T-614 is a novel antiinflammatory compound with different pharmacological properties from that of the reference drugs.
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PMID:Pharmacological studies of the new antiinflammatory agent 3-formylamino-7-methylsulfonylamino-6-phenoxy-4H-1-benzopyran-4-o ne. 1st communication: antiinflammatory, analgesic and other related properties. 141 59


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