Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.2.1.31 (beta-glucuronidase)
 7,680 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The nature of the compartmentalization of catalase in human myeloid cells is an unresolved issue. Using a rabbit polyclonal antibody specific for catalase, indirect immunocytofluorescence of immature leukemic promyelocytes (HL-60 cells) showed a pattern of small, sharp, punctate staining in the cytoplasm of all cells, while mature neutrophils showed a larger diffuse, flocculent pattern of cytoplasmic staining. Differential centrifugation of nitrogen cavitates of HL-60 cells indicated that the putative catalase-containing compartment was relatively fragile compared with the compartment(s) that contained myeloperoxidase (MPO), beta-hexosaminidase, beta-glucuronidase, and lysosomal alpha-mannosidase activities. Parallel studies using dimethylsulfoxide (DMSO)-induced HL-60 cells and mature neutrophils showed that, in the course of differentiation, there was an apparent shift in the localization of catalase from the granule fraction to the cytosolic fraction. Percoll-sucrose density gradient centrifugation of HL-60 cell cavitates showed a catalase-containing compartment with a mean peak density (1.05 g/mL) significantly lower than that of the major myeloperoxidase-containing compartment (1.08 g/mL); in mature neutrophils, catalase activity comigrated with lactate dehydrogenase (LDH) activity. Catalase in isolated fractions was protected from proteolysis in the absence, but not in the presence, of 0.1% Triton X-100. Digitonin titration experiments confirmed the compartmentalized nature of catalase in immature HL-60 cells and were consistent with a cytosolic localization in mature neutrophils. Ultrastructural localization of catalase by Protein A-gold immunocytochemistry demonstrated four to six catalase-containing compartments in all HL-60 cell profiles. In mature neutrophils, catalase was localized primarily in the cytoplasmic matrix, although in fewer than 2% of the cell profiles, one to two catalase-containing compartments were observed. The changes in catalase localization that occur during myeloid differentiation appear to be similar to the changes that occur during erythroid and megakaryocytic differentiation, and may have potential clinical significance in the classification of acute leukemia and in the development of drug resistance.
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PMID:Changes in the localization of catalase during differentiation of neutrophilic granulocytes. 816 45

Many genes mapping to pigmentation loci are involved in the regulation of melanin synthesis in the mouse. The brown (b) locus controls black/brown coat coloration, and its product has significant homology to the key melanogenic enzyme tyrosinase. This has led to suggestions that the b-protein is itself a melanogenic enzyme. In order to investigate its function, we have established lines of mouse fibroblasts stably expressing the b-protein by co-transfection of a b-protein expression vector and a plasmid conferring resistance to the antibiotic G418. The b-protein synthesised by these cells has the expected molecular mass of 75 kDa and reacts with three different anti-b-protein antibodies. We were unable to confirm previous reports that the b-protein has tyrosinase or catalase activity, but detected stereospecific dopachrome tautomerase activity in b-protein-expressing fibroblasts. This dopachrome tautomerase binds to Concanavalin A-Sepharose, and the major product of its action on L-dopachrome is 5,6-dihydroxyindole-2-carboxylic acid. Since this activity is not present in untransfected cells we conclude that the b-protein has dopachrome tautomerase activity. Fibroblasts do not contain melanosomes, the specialised organelles in which the b-protein is located in melanocytes. Nevertheless, indirect immunofluorescence localisation of the b-protein in transfected fibroblasts produces a distinctive pattern of intense juxtanuclear staining combined with punctate cytoplasmic staining. Double-labelling shows co-localisation of the b-protein with the late endosomal/lysosomal markers beta-glucuronidase and LAMP-1, both in transfected fibroblasts and in mouse melanoma cells. These findings are consistent with the hypothesis that melanosomes are closely related to lysosomes.
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PMID:The mouse brown (b) locus protein has dopachrome tautomerase activity and is located in lysosomes in transfected fibroblasts. 827 Jun 21

In order to evaluate the functions of granulocytes, cytochemical reactions to alkaline and acid phosphatases, beta-glucuronidase, myeloperoxidase and catalase were performed in leukocyte concentrate smears for 45 overhaul workers of a chemical plant producing pesticides. As compared to the control group of 24 unexposed healthy individuals living in the plant area, the alkaline phosphatase and catalase reactions were weaker; the leukocyte count was slightly elevated; the differential white blood cell count did not show any significant changes, only the percentage of monocytes was slightly reduced. The results of our studies can testify a slight impairment of leukocyte function in workers exposed to chemical pesticides.
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PMID:[Cytoenzymatic examinations of peripheral blood granulocytes in overhaul workers of the chemical plant "Organika-Jaworzno" at Jaworzno]. 849 98

The biochemical basis for the cancer chemopreventive and anti-cancer activities of glucarate, retinoids (13-cis-retinoic acid, hydroxyphenyl retinamide) and their synergistic combination, has been evaluated. Neither alone nor in combination did these agents affect the level in the rat, of enzymes which are (a) known to correlate with reduced risk of carcinogenesis (detoxification enzyme, catalase, glutathione reductase) nor (b) enzymes which correlate with increased risk of carcinogenesis (beta-glucuronidase, xanthine oxidase, glucose-6-phosphate dehydrogenase). Retinoids, but neither glucarate nor its lactone inhibited free radical-induced lipid peroxidation. Both agents alone and synergistically in combination, raise cellular cAMP levels, repress protein kinase C and more generally inhibited DNA synthesis.
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PMID:Basis for the anti-tumor and chemopreventive activities of glucarate and the glucarate:retinoid combination. 851 53

Deletion analysis of the promoter region of a gene for catalase, cat2, from castor bean (Ricinus communis) was performed to identify the cis-regulatory elements responsible for the expression of a beta-glucuronidase (GUS) fusion gene during seed formation and postembryonic development in transgenic tobacco. The analysis showed that multiple cis-elements contribute to the activity of the cat2 promoter during seed formation and postembryonic development. The 5'-upstream regions from -1,241 to -816 bp, from -720 to -682 bp, and from -632 to -535 bp, relative to the site of initiation of translation of cat2, contributed positively to the activity of the cat2 promoter during both stages. By contrast, the region from -816 to -720 bp had a negative effect at both stages. The region from -682 to -632 bp contributed positively to the activity during seed formation but negatively during postembyonic development. Histochemical analysis revealed that the multiple cis-elements determined not only the level of expression of the chimeric gene but also the tissue-specificity of such expression. For example, the region from -1,241 to -816 bp allowed expression of the chimeric gene in the axis of the embryo of the dry seed, as well as in the cortex of the middle part of the hypocotyl and at the base of epicotyl in the young seedling.
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PMID:Different sets of cis-elements contribute to the expression of a catalase gene from castor bean during seed formation and postembryonic development in transgenic tobacco. 852 6

We isolated and sequenced a genomic clone (CatA) encoding CAT-A catalase, a homologue of the maize catalase isozyme 3 (CAT-3) from rice (Oryza sativa L.). The 5'-upstream non-coding region had very low similarity with the maize Cat3 gene and possible cis elements and sequence motifs in the maize Cat3 gene were not evident, except for TATA and CAAT motifs. Several sequence motifs found in the promoters of plant seed-specific genes were identified in the 5'-upstream non-coding region of the CatA gene. Northern blotting showed that the CatA gene is expressed at high levels in seeds during early development and also in young seedlings. Methyl viologen (paraquat) resulted in the 3-fold induction of the CatA gene in the leaves of young seedlings, whereas abscisic acid, wounding, salicylic acid, and hydrogen peroxide had no or only slight effects. The 1.9 kb 5'-upstream fragment (-1559 to +342) of the CatA gene was fused with the Escherichia coli beta-glucuronidase (GUS) gene and introduced by electroporation into protoplasts prepared from rice suspension-cultured cells, then the transient expression of the GUS gene was examined. Deletion analysis of this chimeric gene suggested that a weak silencer is located in the region between -1564 to -699. Abscisic acid (ABA) at a final concentration of 10(-6) M doubled GUS activity in protoplasts electroporated with the chimeric DNAs having 1.9 to 1.2 kb 5'-upstream regions. A sequence highly similar to the Sph box, a motif found in genes modulated by ABA, was found at -266 to -254. Deletion of this region however, did not eliminate the responsiveness to ABA. Expression of the chimeric gene in the protoplasts was not enhanced by stress such as low and high temperature, hydrogen peroxide, methyl viologen, salicylic acid, elicitor, and UV light. The chimeric CatA-GUS plasmid DNAs amplified in the methylation-positive strain, E. coli DH5alpha, showed GUS gene activities, whereas all the chimeric DNAs amplified in the methylation-deficient E. coli JM110 were completely inactive in the presence or absence of ABA in the culture medium. DNA methylation, especially of either one or both of the deoxyadenosines at the two GATC motifs (one in the first exon and the other in the first intron of the rice CatA gene), appeared to be responsible for the CatA promoter activity identified in the transient assay.
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PMID:Cloning and characterization of the rice CatA catalase gene, a homologue of the maize Cat3 gene. 860 2

The present study analyzed the association between two major processes that occur during atherogenesis: macrophage activation and peroxidation of the cellular lipids. Macrophage activation was achieved by cell incubation with phorbol myristate acetate (PMA) for 24 h at 37 degrees C, and was determined as: a) PMA concentration-dependent increment in the release of beta-glucuronidase, b) decrement in the procoagulant activity, and c) increment in the release of superoxides from the cells. PMA-induced macrophage activation was accompanied by cellular lipid peroxidation, as measured by increased formation of lipid peroxides (by 435%), thiobarbituric acid-reactive substances (TBARS) (by 26%), and conjugated dienes (by 77%) in comparison with control nonactivated cells. The maximal effect of PMA on lipid peroxidation in macrophages was achieved within 1 h of cell incubation with PMA. This effect was demonstrated in J-774 A.1 macrophages, as well as in mouse peritoneal, macrophages, U-937 and P-338 macrophage cell lines. Upon incubation of macrophages with 4 alpha phorbol 12, 13 didecanoate, an analogue of PMA (which, unlike PMA, does not activate protein kinase C), macrophage lipid peroxidation was lower compared with PMA, suggesting a role for protein kinase C in cellular lipid peroxidation. Analysis of cellular antioxidants under PMA-induced macrophage activation revealed a decrease of 50% in total glutathione, and in catalase levels following treatment with 100 nM PMA compared with control cells. In summary, our study demonstrates that PMA-activated macrophages undergo significant lipid peroxidation, which is associated with reduced activity of the cellular antioxidative system.
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PMID:Macrophage activation with phorbol myristate acetate is associated with cellular lipid peroxidation. 868 55

In order to assess the immunological system of the chemical plant workers certain rates of cellular and humoral immunity were estimated. The study group was composed of 19 males employed in the production of liquid pesticides, and 18 females performing ancillary jobs and handling closed containers. They were alternatively exposed to phosphoroorganic compounds and pyrethroides, and to chlorinated hydrocarbons, carbamates, nitrophenols and organic solvents, however exposure to the latter was lower. Chronic bronchitis was observed in 7 (37%) males and 4 (22%) females. Serum concentrations of immunoglobulins G, A and M, complement protein Cs, and circulating immune complexes were estimated. The peripheral blood leukocyte count and percentage, the granulocyte adherence and phagocytic activity, spontaneous NBT-dye reduction as well as cytochemical reactions to alkaline and acid phosphatase, beta-glucuronidase, myeloperoxidase and catalase of neutrophils were evaluated; the lymphocyte subpopulations CD3, CD4, CD8, CD16 were also estimated. As compared to controls, a significantly increased serum IgG concentration was found, together with elevated IgM in males and IgA in females. The leukocyte count in males was significantly higher. A considerable decrease in the percentage of neutrophils was accompanied by a significantly greater spontaneous NBT-dye reduction in both groups. Neutrophil adherence impairment was observed in males. Cytochemical reactions to beta-glucuronidase and catalase in both sexes, to alkaline and acid phosphatase in females, and to myeloperoxidases in males were significantly lowered, whereas the reaction to acid phosphatase in males was significantly enhanced. The percentages of lymphocytes CD3, CD4 and the CD4/CD8 ratio were significantly decreased.
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PMID:Humoral and cellular immunity rates in chemical plant workers employed in the production of liquid pesticides. 880 24

The effect of curcumin on the biochemical changes induced by isoproterenol (ISO) administration in rats was examined. ISO (300 mg Kg-1 administered subcutaneously twice at an interval of 24 h) caused a decrease in body weight and an increase in heart weight, water content as well as in the levels of serum marker enzymes viz creatine kinase (CK), lactate dehydrogenase (LDH) and LDH1 isozyme. It also produced electrocardiographic changes such as increased heart rate, reduced R amplitude and ST elevation. Curcumin at a concentration of 200 mg.Kg-1, when administered orally, showed a decrease in serum enzyme levels and the electrocardiographic changes got restored towards normalcy. Myocardial infarction was accompanied by the disintegration of membrane polyunsaturated fatty acids expressed by increase of thiobarbituric acid reactive substance (TBARS), a measure of lipid peroxides and by the impairment of natural scavenging, characterized by the decrease in the levels of superoxide dismutase, catalase, glutathione peroxidase, ceruloplasmin, alpha tocopherol, reduced glutathione (GSH) and ascorbic acid. The oral pretreatment with curcumin two days before and during ISO administration decreased the effect of lipid peroxidation. It was shown to have a membrane stabilizing action by inhibiting the release of beta-glucuronidase from nuclei, mitochondria, lysosome and microsome. Curcumin pre- and co-treatment decreased the severity of pathological changes and thus, could have a protective effect against the damage caused by myocardial infarction (MI).
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PMID:Protective role of curcumin against isoproterenol induced myocardial infarction in rats. 885 58

It has been demonstrated that the carboxyl terminus of microbody enzymes functions as a targeting signal to microbodies in higher plants. We have examined an ability of 24 carboxy-terminal amino acid sequences to facilitate the transport of a cytosolic passenger protein, beta-glucuronidase, into microbodies in green cotyledonary cells of transgenic Arabidopsis. Immunoelectron microscopic analysis revealed that carboxy-terminal tripeptide sequences of the form [C/A/S/P]-[K/R]-[I/L/M] function as a microbody-targeting signal, although tripeptides with proline at the first amino acid position and isoleucine at the carboxyl terminus show weak targeting efficiencies. All known microbody enzymes that are synthesized in a form similar in size to the mature molecule, except catalase, contain one of these tripeptide sequences at their carboxyl terminus.
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PMID:Changes in targeting efficiencies of proteins to plant microbodies caused by amino acid substitutions in the carboxy-terminal tripeptide. 924 91


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