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 polypeptides of purified preparations of the coronavirus responsible for transmissible gastroenteritis of pigs have beem examined by polyacrylamide gel electrophoresis. Four major polypeptides, VPI (mol. wt. 200000), VP2 (50 000), VP3 (30000) and VP4 (28500) and two minor polypeptides, VPIa (105000) and VPIb (80500) have been reproducibly demonstrated in the virion, of which VPI, VP3 and VP4 contain carbohydrate. Treatment of the virion with the proteolytic enzyme bromelain removes the surface projections and VPI, thus identifying this glycopolypeptide as the major structural component of the projection.
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PMID:The polypeptide structure of transmissible gastroenteritis virus. 17 35

The ascites form of a chemically induced guinea pig hepatoma, line-10, was resistant to killing in vitro by xenogeneic antibody and guinea pig complement. Pretreatment of line-10 cells with certain proteolytic enzymes rendered tham susceptible to the killing action of antibody and guinea pig complement. The effects of enzyme pretreatment were dependent on enzyme concentration, temperature, and could be blocked by addition of competitive or non-competitive inhibitors. The effect of the enzyme treatment could reversed by incubating the treated cells at 37 degrees C (but not at 0 degrees C), in the absence of the enzyme. Effective enzymes included ficin, bromelain, pronase, elastase, papain, trypsin, collagenase, lipases type I and type VI, and the neuraminidase preparation isolated from Clostridium perfringens. The activity of the lipase preparations and the neuraminidase preparation isolated from Clostridium perfringens appeared to be caused by proteolytic enzyme contamination. Enzyme preparations that proved ineffecitve in rendering the line-10 cells sensitive to killing by antibody and guinea pig complement included DNase, RNase, beta-glucuronidase type 6A or type B10, hyaluronidase type V or type VI, and pectinesterase.
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PMID:Lysis of tumor cells by antibody and complement. VI. Enhanced killing of enzyme-pretreated tumor cells. 17 70

Purified avian infectious bronchitis virus was digested with bromelain (0.7 mg/ml), and the surface projections were removed. Polyacrylamide gel electrophoresis of the polypeptides from these bromelain-treated particles showed that VP1, VP2, and VP5 were missing from the seven polypeptides. VP1 to VP7, that were present in untreated virus preparations. Milder bromelain treatment (0.07 mg/ml) left visible surface projections and polypeptides comprising VP1 and VP2 intact, but removed VP5. Thus, there are apparently two types of surface projections on the virus particle. The ribonucleoprotein complex was released from virus particles disrupted with 1% Nonidet P-40. The proportion of VP6 in such preparations was greatly reduced, implying that VP6 is the structural polypeptide of the ribonucleoprotein. Polypeptides VP1, VP2, VP4, and VP5 are glycosylated, but none of the polypeptides contains lipid.
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PMID:Polypeptides of the surface projections and the ribonucleoprotein of avian infectious bronchitis virus. 20 78

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

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

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

Normal mice spontaneously develop plaque-forming cells (PFC) specific for antigens on modified self erythrocytes (bromelain-treated mouse erythrocytes [BrMRBC] antigens). Our study demonstrates that the sex-linked defect that results in the inability of CBA/N mice to respond to several T-independent antigens (TI-2 antigens) also regulates the autoantibody response to BrMRBC antigens. Thus, in CBA/N homozygous mice and male F1 offspring of CBA/N-mothered crosses, e.g., (CBA/N X NZB)F1 males, such PFC are absent. To examine whether specific autoreactive B cells are present in defective mice, the latter were stimulated either nonspecifically with the mitogen LPS or by infection with lethal malaria (17XL Plasmodium yoelii) known to induce anti-BrMRBC PFC specifically. The results indicate that modest antibody responses to self antigens could be induced in young (5- to 7-wk old) defective mice and that these responses increased as a function of age. The data is consistent with the view that the defect in CBA/N mice does not result from an absence of functional anti-BrMRBC B cells but rather from low frequencies of the specific precursors, which can be triggered and expanded with age probably by environmental stimulations.
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PMID:Influence of the sex-linked defect in CBA/N mice on autoimmune responses to isologous erythrocytes. Ability to overcome the defect with age. 31 95

CBA/N mice carry an X-linked recessive defect expressed in cells of the B cell lineage. The major deficiency in these mice is an almost complete inability to respond to certain thymus-independent antigens, such as pneumococcal polysaccharide type III (S III). We have examined the responses of mice carrying the CBA/N X-chromosome to the malaria parasite Plasmodium yoelii and the piroplasm Babesia microti. We have found that the duration and severity of these infections is increased in mice carrying the CBA/N X-chromosome and that this is associated with a markedly defective IgM antibody response to the parasitized red cell and a failure to produce autoantibodies to bromelain-treated mouse RBCs. An autoimmune response directed at modified determinants on the red cell membrane may be one of the factors involved in the control of these infections.
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PMID:Immunity to Plasmodium yoelii and Babesia microti: modulation by the CBA/N X-chromosome. 31 44

The activity of Nocardia water-soluble mitogen (NWSM) and LPS were compared in several experimental systems, since both compounds are B-cell mitogens and polyclonal activators in vitro. The results reported here demonstrated that NWSM like LPS also has a strong adjuvant activity in vivo if administered in saline with a strong antigen (heterologous red blood cells) or even with a weak immunogen such as theta alloantigen. However, in contrast to LPS, NWSM administered to mice failed to induce in vivo proliferation of lymphocytes, polyclonal activation and PFC against syngeneic bromelain-treated erythrocytes and thymocytes. It is possible therefore, that different mechanisms may be responsible for adjuvant activity of NWSM and LPS.
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PMID:Nocardia water-soluble mitogen and lipopolysaccharide. Comparative study of two adjuvants and B-cell mitogens in mice. 32 90

A quantitative method for measuring pain threshold by the use of ultrasonic stimulation in man was designed and the possibility of clinical application in assessing analgesics was investigated. Ultrasonic stimulus was given to Japanese subjects on the palmer distal part of the 2nd, 3rd and 4th fingers of both hands. The latent time between start of the stimulation and withdrawal of the hand when perceiving pain was considered the pain threshold. The ultrasonic evoked pain was a sharp pin-prick type, without sensations such as thermal and mechanical. The pain threshold lowered with increasing either stimulus intensity or water bath temperature when the hand of the subject was immersed during measurement. Normal threshold to ultrasonic stimulation measured in both 50 men and 50 women gave nearly normal distribution curves; women being more sensitive to ultrasonics than men. Analgesia with codeine phosphate (20 mg p.o.), aspirin (1.5, 1.0, 0.5 g p.o.), aminopyrine (100 mg p.o.) and mefenamic acid (500 mg p.o.) in volunteers of both sexes was demonstrated significantly using this method under double blind circumstances. Pentobarbital, diazepam, butylscopolamine, bromelain and placebo each in the usual dose used clinically failed to alter the pain threshold. Humans were at least 25 fold more sensitive than mice to the analgesics used herein.
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PMID:Clinical assessment of analgesics using ultrasonic stimulation. A new method. 33 41


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