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

Activities of acid phosphatase, beta-glucuronidase, N-acethyl-beta-D-glucosaminidase and acid beta-galactosidase were investigated histochemically in rabbit corneas. Frozen sections after block fixation in cold 4% formaldehyde with 1% CaCl2 followed by washing in cold physiological saline as well as cold microtome sections of corneas quenched in petroleter chilled with acetone-dry ice mixture, transferred to nonprecooled slides or semipermeable membranes were used. Standard aqueous media were employed in the case of free-floating frozen sections of fixed corneas as well as of cold mictrotome sections (postfixed in cold 4% formaldehyde). Agar media were used in connection with the technic of semipermeable membranes. Gomori method (in the case of acid phosphatase), simultaneous azocoupling methods (substrates derivated of naphthol-AS-BI with hexazonium-p-rosanilin) in the case of acid phosphatase, beta-glucuronidase and N-acetyl-beta-D-glucosaminidase and the indigogenic method in the case of acid beta-galactosidase were applied. Enzyme activities in sections of fixed corneas were minimal in comparison with those in cold microtome sections of unfixed material revealed particularly with the technic of semipermeable membranes which is to be preferred. This technic is recommended in studies concerned with lysosomal enzymes in the cornea, particularly in keratocytes. All enzymes investigated were present in corneal epithelium, keratocytes and endothelium. Acid phosphatase displayed the highest activity followed by beta-glucuronidase and acetyl-beta-D-glucosaminidase. The activity of beta-galactosidase was the lowest. For the demonstration of activities in keratocytes sections parallel to the surface are very suitable. In these sections enzyme activities were demonstrated in small granules (apparently lysosomes) present in the central part of their cytoplasm as well as in projections. Diffuse staining was also seen, being the highest in the case of acid phosphatase.
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PMID:Distribution of acid phosphatase, beta-glucuronidase, n-acetyl-beta-d-glucosaminidase and beta-galactosidase in cornea of albino rabbit. 5 44

In human neutrophils, the chemotactic peptide N-formyl-L-methionyl-L-leucyl-L-phenylalanine (fMLP) induces increases in the intracellular free Ca2+ concentration ([Ca2+]i) with subsequent activation of beta-glucuronidase release and superoxide (O2-) production. Results from several laboratories suggest that the increase in [Ca2+]i is due to activation of non-selective cation (NSC) channels. We studied the biophysical characteristics, pharmacological modulation and functional role of NSC channels in dibutyryl cyclic AMP (Bt2cAMP)-differentiated HL-60 cells. fMLP increased [Ca2+]i by release of Ca2+ from intracellular stores and influx of Ca2+ from the extracellular space. fMLP also induced Mn2+ influx. Ca2+ and Mn2+ influxes were inhibited by 1-(beta-[3-(4-methoxyphenyl)propoxy]-4-methoxyphenethyl)-1H-imidazole hydrochloride (SK&F 96365). Under whole-cell voltage-clamp conditions, fMLP and ATP (a purinoceptor agonist) activated inward currents characterized by a linear current-voltage relationship and a reversal potential near 0 mV. NSC channels were substantially more permeable to Na+ than to Ca2+. SK&F 96365 inhibited fMLP- and ATP-stimulated currents with a half-maximal effect at about 3 microM. Pertussis toxin prevented stimulation by fMLP of NSC currents and reduced ATP-stimulated currents by about 80%. Intracellular application of the stable GDP analogue, guanosine 5'-O-[2-thio]diphosphate, completely blocked stimulation by agonists of NSC currents. In excised inside-out patches, single channel openings with an amplitude of 0.24 pA were observed in the presence of fMLP and the GTP analogue, guanosine 5'-O-[3-thio]triphosphate. The bath solution contained neither Ca2+ nor ATP. The current/voltage relationship was linear with a conductance of 4-5 pS and reversed at about 0 mV. fMLP-induced beta-glucuronidase release and O2- production were substantially reduced by replacement of extracellular CaCl2 or NaCl by ethylenebis(oxyethylenenitrilo)tetra-acetic acid and choline chloride respectively. In the absence of Ca2+ and Na+, fMLP was ineffective. SK&F 96365 inhibited fMLP-induced beta-glucuronidase release and O2- production in the presence of both Ca2+ and Na+, and in the presence of Ca2+ or Na+ alone. NaCl (25-50 mM) enhanced the basal and absolute extent of fMLP-stimulated GTP hydrolysis of heterotrimeric regulatory G-proteins in HL-60 membranes. The order of effectiveness of salts in enhancing GTP hydrolysis was LiCl > KCl > NaCl > choline chloride.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Formyl peptides and ATP stimulate Ca2+ and Na+ inward currents through non-selective cation channels via G-proteins in dibutyryl cyclic AMP-differentiated HL-60 cells. Involvement of Ca2+ and Na+ in the activation of beta-glucuronidase release and superoxide production. 128 79

alpha-Thrombin induces a dose-dependent rapid transient increase in platelet cytosolic Ca2+ levels, coming solely from intracellular stores, since EGTA has no effect. In contrast, the post-stimulation equilibrium [Ca2+]in depends upon an influx from the extracellular milieu, and is lower in the presence of EGTA. We measured the Ca2+ transient (with Indo-1, 1-[2-amino-5-(6-carboxyindol-2-yl)-phenoxy]-2-(2'-amino-5'-methylp henoxy)- ethane-N,N,N',N'-tetraacetic acid), cytosolic alkalinization (with BCECF, 2',7-bis-(2-carboxyethyl)-5(and 6)-carboxyfluorescein), membrane depolarization (with diS-C3-(5), 3,3'-dipropylthiodi-carbocyanide iodide), and degranulation (by beta-glucuronidase release) induced in washed human platelets by 9 nM thrombin in the absence or presence of extracellular or intracellular Ca2+ chelating agents (EGTA and BAPTA, 5,5'-dimethyl-bis-(o-aminophenoxy)-ethane-N,N,N',N'-tetraacetic acid, respectively). Platelets loaded simultaneously with 2 microM Indo-1 and 15 microM BAPTA (each as the acetoxymethyl ester) before addition of thrombin exhibited no cytoplasmic Ca2+ transient or alkalinization, no depolarization or degranulation. Replenishment of such cells with extracellular CaCl2 restored resting [Ca2+]in. Upon stimulation with 9 nM thrombin these replenished platelets exhibited no Ca2+ transient, and a slow gradual increase in [Ca2+]in from extracellular stores, a slow alkalinization and depolarization, and partial degranulation, all abolished by extracellular EGTA. Thus thrombin-induced platelet activation exhibits a biphasic Ca2+ requirement: the initial transient increase in [Ca2+]in comes from intracellular stores only, while the later steps of depolarization, alkalinization, and degranulation can proceed, albeit more slowly, if only extracellular Ca2+ is available.
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PMID:Cytoplasmic Ca2+ is necessary for thrombin-induced platelet activation. 251 Nov 90

Permeabilization of human neutrophils has been accomplished by using saponin, a cholesterol complexing agent, permitting experimental manipulation of the intracellular milieu. Access of ordinarily impermeable solutes, such as [14C]-inulin or [14C]-sucrose, to the water space of the cells was considered the main criterion for permeabilization. Other criteria were substantial (50 to 80%) release of cytoplasmic lactate dehydrogenase and permeability to trypan blue. Successful permeabilization did not cause substantial release of the granule enzymes lysozyme or beta-glucuronidase. Washing the neutrophils, to remove soluble saponin and released cytoplasmic contents, and resuspension did not alter their permeabilized character. By supplementing the medium with CaCl2, thereby obtaining free Ca2+ concentrations of 1.5 X 10(-7) M to 10(-4) M, it was possible to stimulate lysozyme secretion from washed or unwashed permeabilized neutrophils. A total of 20 to 30% of the total cellular lysozyme was released during an incubation of 5 min at 37 degrees C. Secretion was inversely related to cell concentration. No beta-glucuronidase was secreted under these conditions and no response was obtained by using unpermeabilized cells. Thus, permeabilized neutrophils respond to increases in free Ca2+ alone, without resorting to conventional secretagogues. This system also permits the manipulation of intracellular constituents important for stimulus-response coupling.
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PMID:Micromolar concentrations of free calcium provoke secretion of lysozyme from human neutrophils permeabilized with saponin. 396 35

We developed a polyethylene glycol (PEG)-mediated direct DNA transfer method from intact Saccharomyces cerevisiae spheroplasts into Arabidopsis thaliana protoplasts. To monitor the DNA transfer from yeast to plant cells, beta-glucuronidase (GUS) reporter gene in which a plant intron was inserted was used as a reporter. This intron-GUS reporter gene on a 2 microns-based plasmid vector was not expressed in yeast transformants, while it expressed GUS activity when the plasmid DNA was introduced into plant cells. When a mixture of 1 x 10(8) of S. cerevisiae spheroplasts harboring the plasmid and 2 x 10(6) of A. thaliana protoplasts was treated with PEG and high pH-high Ca2+ solution (0.4 M mannitol, 50 mM CaCl2, 50 mM glycine-NaOH pH 10.5), GUS activity was detected in the extract of the plant cells after a three-day culture. The GUS activity was higher than that of a reconstitution experiment in which the mixture of 1 x 10(8) of S. cerevisiae spheroplasts which did not carry the reporter gene, 2 x 10(6) of A. thaliana protoplasts and the same amount of the reporter plasmid DNA as that contained in 1 x 10(8) of S. cerevisiae spheroplasts, was treated with PEG and high pH-high Ca2+ solution. Moreover, the GUS gene expression was resistant to micrococcal nuclease treatment before and during PEG treatment. From these results, we concluded that plasmid DNA can be directly transferred from intact yeast spheroplasts to plant protoplasts by a nuclease-resistant process, possibly by the cell fusion.
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PMID:Direct transfer of plasmid DNA from intact yeast spheroplasts into plant protoplasts. 806 37

beta-Glucuronidase was purified 360-fold from Escherichia coli HGU-3, an human intestinal bacterium. The specific activity of the purified enzyme was 17.78 units/mg protein. The enzyme (M.W. 290000) is composed of four subunits (M.W. 72000) with a pI and optimal pH of 4.8 and 6-7, respectively. The apparent Km for p-nitrophenyl-beta-D-glucuronide was found to be 0.22 mM. The enzyme was inhibited by saccharic acid 1,4-lactone, glycyrrhizin, N-ethylmaleimide (NEM) and p-chloromercuriphenylsulfonic acid (PCMS). Using the bile containing bilirubin diglucuronide as a substrate, the purified beta-glucuronidase was able to hydrolyze it to bilirubin. This hydrolyzed bilirubin formed calcium bilirubinate with a reaction mixture containing CaCl2.
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PMID:Purification and characterization of beta-glucuronidase from Escherichia coli HGU-3, a human intestinal bacterium. 884 1

A plasmid pLC-bar containing the bialaphos resistance gene derived from Streptomyces hygroscopicus between the Lentinus edodes ras gene promoter and priA gene terminator was constructed. When protoplasts of Pleurotus ostreatus were mixed with the plasmid DNA in the presence of polyethylene glycol and CaCl2, bialaphos-resistant colonies were obtained. This indicated that transformation was successful. Southern blot analysis of total DNAs from transformants showed that the introduced plasmid DNA was integrated into the host chromosome and partly rearranged. A plasmid, pLC-GUS, containing the Escherichia coli beta-glucuronidase (GUS) gene under the control of the L. edodes ras gene promoter and priA gene terminator was constructed and introduced into protoplasts of P. ostreatus with pLC-bar by co-transformation. Two of 5 transformants obtained as bialaphos-resistant colonies showed two to twenty times higher specific activity of GUS than the recipient. Southern blot analysis of total DNAs from transformants indicated the presence of the GUS gene only in the two transformants. These results indicated that co-transformation of P. ostreatus was successful, and that the GUS gene was expressed in P. ostreatus. This transformation system will enable us to breed commercial strains of P. ostreatus at the molecular level.
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PMID:The integrative transformation of Pleurotus ostreatus using bialaphos resistance as a dominant selectable marker. 890 Nov 6

The nematode-trapping fungus Arthrobotrys oligospora was transformed to hygromycin resistance using the hygromycin-B phosphotransferase gene from Escherichia coli under the control of various heterologous fungal promoters. Plasmid DNA was introduced into fungal protoplasts by polyethylene glycol/CaCl2 treatment. Transformation frequencies varied between 1-6 transformants per microgram DNA. Seven out of 13 integration events analyzed from transformants were single copy integrations, whereas the remaining were multiple and more complex integrations. The addition of restriction enzymes during transformations increased the frequency of single copy integrations. Co-transformation, using the E. coli uidA gene encoding the beta-glucuronidase reporter gene under the control of an Aspergillus nidulans promoter, occurred at frequencies of up to 63%.
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PMID:Transformation of the nematode-trapping fungus Arthrobotrys oligospora. 1022 Aug 88

Transgenic Phytophthora palmivora strains that produce green fluorescent protein (GFP) or beta-glucuronidase (GUS) constitutively were obtained after stable DNA integration using a polyethylene-glycol and CaCl2-based transformation protocol. GFP and GUS production were monitored during several stages of the life cycle of P. palmivora to evaluate their use in molecular and physiological studies. 40% of the GFP transformants produced the GFP to a level detectable by a confocal laser scanning microscope, whereas 75% of the GUS transformants produced GUS. GFP could be visualised readily in swimming zoospores and other developmental stages of P. palmivora cells. For high magnification microscopic studies, GFP is better visualised and was superior to GUS. In contrast, for macroscopic examination, GUS was superior. Our findings indicate that both GFP and GUS can be used successfully as reporter genes in P. palmivora.
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PMID:Green fluorescent protein (GFP) as a reporter gene for the plant pathogenic oomycete Phytophthora palmivora. 1048 25