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)

Dibutyryl cyclic adenosine 3':5'-monophosphate (DBcAMP) has been reported to cause numerous alterations in the activity of hepatic monooxygenase enzymes following in vivo administration or in vitro addition to intact liver preparations. In the present report the effect of the nucleotide on metabolism of p-nitroanisole (pNA) and aniline was studied in isolated rat hepatocytes. Initial studies indicated that in vitro addition of DBcAMP to hepatocytes increased metabolism of both pNA and aniline as determined by the production of oxidized metabolites, p-nitrophenol (pNP) and p-aminophenol, respectively. After enzymatic hydrolysis with beta-glucuronidase and arylsulfatase, it was determined that DBcAMP had increased accumulation of pNP formed from pNA by inhibiting further metabolism via conjugation reactions. Further studies using pNP directly as substrate confirmed the finding and revealed that glucuronidation was more sensitive to the inhibitory effect of DBcAMP than was sulfation. The 8-bromo derivative of cAMP was more potent than DBcAMP at inhibiting glucuronidation, whereas cyclic AMP and dibutyryl cyclic guanosine 3':5'-monophosphate were without effect. Noncyclic adenine nucleotides (ATP, ADP, AMP) also altered pNA and pNP metabolism. ATP and ADP increased pNP accumulation from pNA while ATP and AMP inhibited glucuronidation of pNP. DBcAMP was further found to decrease UDP-glucuronic acid levels in a concentration-dependent manner without disrupting the redox state (NAD+/NADH) in hepatocytes. The data suggest that adenine nucleotides exert a nonspecific inhibition upon glucuronidation and sulfation reactions.
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PMID:Inhibition of glucuronidation and sulfation by dibutyryl cyclic AMP in isolated rat hepatocytes. 287 57

Within the uterine glands, the following enzymes were demonstrated by histochemical methods after 30, 58, 80, 100, and 110 d of pregnancy, respectively: beta-N-acetyl-hexosaminidase, beta-galactosidase, beta-glucuronidase, alpha-mannosidase, acid phosphatase, alkaline phosphatase, esterases, cytochrome oxidase, 5-nucleotidase, leucine aminopeptidase, adenosine triphosphatase, diaphorases (NADH, NADPH), glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase, succinate dehydrogenase, isocitrate dehydrogenase (NAD, NADP), beta-hydroxybutyrate dehydrogenase, glycero-3-phosphate dehydrogenase, NAD-glycero-3-phosphate dehydrogenase, glutamate dehydrogenase (NAD, NADP), lactate dehydrogenase. The results show that the activities of G-6-PDH, 6-PGDH, and cytochrome oxidase increase within secreting cells during the 2nd half of pregnancy. The activities of the other enzymes remained almost unchanged during the period of investigation. The description of our results distinguishes between gland neck, middle, and distal part of the secretory unit, respectively. In general, the enzyme activities are similar within the middle and distal gland segments, but lower in the epithelia of the neck region. The activity of dehydrogenases was medium to intensive within the middle and distal gland segments, but only low to medium within the neck portion. Of the hydrolases, the acid phosphatase, ATPase, leucine aminopeptidase, and beta-galactosidase demonstrated an intensive activity within activity secreting cells. The enzyme activities of the gland epithelia are compared with these of the uterine surface epithelia and the histochemical results are discussed in context with their significance in histiotrophic nutrition.
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PMID:[Enzyme histochemistry of the pig placenta. III. Histotopics of enzymes in the uterine epithelium]. 309 49

In studies designed to reexamine the in vivo occurrence of retinyl phosphate mannose we injected hamsters intraperitoneally with either [2-3H]mannose or [15-3H]retinol and sacrificed the animals 15 min later. The small intestine was removed, the epithelial cells were scraped, and a methanolic extract of the labeled cells was prepared and chromatographed on a Mono Q anion-exchange column. Intraperitoneal administration of either [2-3H]mannose or [15-3H]retinol lead to the formation of a tritium-labeled anionic compound with a retention time on the Mono Q column similar to that of standard retinyl phosphate mannose. However, the biochemical properties of this labeled anionic compound were those expected of an organic acid and not retinyl phosphate mannose. The compound was resistant to both strong acid hydrolysis and mild base hydrolysis, as well as digestion with alpha- or beta-mannosidase, phosphodiesterase I, nucleotide pyrophosphatase, or beta-glucuronidase. When chromatographed on an Aminex HPX-87H organic acid analysis column or a silicic acid column the labeled anionic compound derived from either [2-3H]mannose or [15-3H]retinol comigrated with standard lactic acid. Treatment of the anionic compound derived from [2-3H]mannose with lactate oxidase or L-lactate 2-monooxygenase resulted in the formation of a tritium-labeled product that cochromatographed, respectively, with pyruvate or acetate on the Aminex HPX-87H column. However, treatment of the anionic compound derived from [15-3H]retinol with these same two enzymes resulted in a labeled product that migrated on the Aminex column at the same position as tritiated water. This result demonstrated that the labeled hydrogen was removed during enzymatic digestion and suggested that it was present on the second carbon of lactic acid. During the course of these studies no evidence for the in vivo labeling of a compound with the properties of retinyl phosphate mannose was found. Since [2-3H]mannose leads to labeled lactic acid in vivo the tritium label must not always be lost, as expected, during the entry step into glycolysis in which mannose 6-phosphate is converted to fructose 6-phosphate. The results suggest that an intramolecular hydrogen transfer from the C-2 position of mannose 6-phosphate to the C-1 position of fructose 6-phosphate can occur during the phosphomannose isomerase reaction. The finding that the position of the tritium label on lactic acid derived from [15-3H]retinol is on the second carbon is consistent with it coming from NADH labeled with tritium in the transferable hydrogen which was formed intracellularly during the NAD+-linked oxidation of retinol to retinaldehyde.
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PMID:In vivo formation of tritium-labeled lactic acid from [2-3H]mannose or [15-3H]retinol by hamster intestinal epithelial cells. 357 14

Filter-paper strips were used to collect GCF, and the sample eluted into a larger volume of diluent. This procedure allows for detection of site-to-site variation in GCF volume, and provides a 300-400 microliter sample for analysis of lactate dehydrogenase (LDH), beta-glucuronidase (BG) and arylsulphatase (AS) activities by a standard (serum) spectrophotometric assay modified for increased sensitivity. The results indicate that although the standard assay for LDH (based on oxidation of NADH) was adequate for detecting low activity in GCF samples, the modification doubled the sensitivity and allowed the use of less sample volume, thereby providing additional material for other assays. The standard assay for BG based on phenolphthalein being generated from phenophthalein glucuronic acid was not adequate for use in GCF analysis. The modification used increased assay sensitivity five-fold and allowed smaller samples to be used. The serum assay for AS (conversion of nitrocatechol sulphate to nitrocatechol) was accurate to the lower limit of AS activity in GCF and could be used without modification. The results emphasize the need to evaluate critically standard spectrophotometric assays for sensitivity when studying physiologically-collected GCF.
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PMID:Evaluation and modification of spectrophotometric procedures for analysis of lactate dehydrogenase, beta-glucuronidase and arylsulphatase in human gingival crevicular fluid collected with filter-paper strips. 388 58

In porcine areolar placental epithelia, the following enzymes were demonstrated by histochemical methods after 30, 58, 80, 100, and 110 d of pregnancy, respectively: beta-N-acetyl-hexosaminidase, beta-galactosidase, beta-glucuronidase, alpha-mannosidase, acid phosphatase, alkaline phosphatase, nonspecific esterases, cytochrome oxidase, 5-nucleotidase, leucine aminopeptidase, adenosine triphosphatase, diaphorases (NADH, NADPH), glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase, succinate dehydrogenase, isocitrate dehydrogenase (NAD, NADP), beta-hydroxybutyrate dehydrogenase, glycero-3-phosphate dehydrogenase, NAD-glycero-3-phosphate dehydrogenase, glutamate dehydrogenase (NAD, NADP), lactate dehydrogenase. The results show that the enzyme activities remained almost unchanged during the period of investigation. Of the dehydrogenases, the diaphorases as well as succinate and lactate dehydrogenase demonstrated generally an intensive activity within the epithelia. The activity of the other dehydrogenases was only low. The activity of unspecific esterase was very intensive within the uterine epithelia but remarkably low within chorionic epithelia. Contrarily, the reaction of adenosine triphosphatase was more intensive within chorionic than uterine epithelia. All investigated glucosidases reacted distinctly positive within chorionic epithelia, but only beta-N-acetyl-hexosaminidase and beta-galactosidase in uterine epithelia. The high activity of acid phosphatase, especially within the chorionic epithelium, seems to be connected with uteroferrin, an iron-binding protein. The histochemical results are discussed in context with the function of the areolae in histiotrophic nutrition and iron transport.
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PMID:[Enzyme-histochemical studies of the pig placenta. II. Histotopics of enzymes in the areolar placenta epithelium]. 392 41

A method for the isolation of intact phagocytic vesicles from guinea pig peritoneal-exudate granulocytes and human peripheral-blood leukocytes is presented. After leukocytes ingested the particles of a stable emulsion of paraffin oil, the uningested emulsion was washed away and the cells were homogenized. The homogenate was placed in the middle of a three-step discontinuous sucrose gradient and centrifuged for 1 hr at 100,000 g. The phagocytic vesicles, containing the low density paraffin-oil particles, were simultaneously washed and collected by floatation, while the other organelles, chiefly granules, sedimented through the lower wash layer, and the particle-free supernatant remained in the middle of the gradient. Emulsion particles stained with Oil Red O were employed to assay the rate of phagocytosis and to mark the location of the particles in subcellular fractions. The dye was extracted from washed cells or cell fractions with dioxane and colorimetrically quantified. The purity of phagocytic vesicles obtained by this method was assessed by electron microscopy, chemical analysis, and assay of enzyme composition. Granule-associated enzymes, acid phosphatase, alkaline phosphatase, beta-glucuronidase, and peroxidase were present in the phagocytic vesicles and originated from the granules. Cyanide-resistant NADH (reduced form of diphosphopyridine nucleotide) oxidase was also found. Enzymes associated with the vesicles exhibited latency to Triton X-100. Uptake of particles and the transfer of total protein and phospholipid into phagocytic vesicles occurred simultaneously Accumulation of acid and alkaline phosphatase in the vesicles continued until phagocytosis ceased. Peroxidase, NADH oxidase, and beta-glucuronidase activities in the phagocytic vesicles, on the other hand, were maximal by 30 min and increased little thereafter even when phagocytosis was still going on.
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PMID:Isolation and properties of phagocytic vesicles from polymorphonuclear leukocytes. 410 63

To determine the localization of several enzymes in Tritrichomonas foetus, the axenic KV-1 strain was grown in Diamond's medium with bovine serum, homogenized in 0.25 M sucrose, and subjected to analytical differential and isopycnic centrifugation. The fractions were assayed for their enzymatic composition and examined electron microscopically. NADH and NADPH dehydrogenases, about 90% of the catalase, and two hydrolases, alpha-galactosidase and manganese-activated beta-galactosidase I are in the nonsedimentable part of the cytoplasm. alpha-Glycerophosphate and malate dehydrogenases are associated with a large particle, whose equilibrium density in sucrose gradients is 1.24. This particle corresponds to that population of the paracostal and paraxostylar granules which, having a uniform granular matrix surrounded by a single membrane, resemble microbodies from other organisms. The small sedimentable portion of catalase (about 10% of the total activity) is not associated with these granules and equilibrates at density 1.22. The nature of the subcellular entity carrying catalase could not be ascertained. Hydrolases with a pH optimum around 6-6.5 (protease, beta-N-acetylglucosaminidase, beta-N-acetylgalactosaminidase, and cation-independent beta-galactosidase II), as well as a large part of acid phosphatase, are associated with a population of large particles which equilibrate at densities from 1.15 to 1.20. The hydrolases in these granules lose their structure-bound latency easily after freezing and thawing. These particles correspond to another population of the paracostal and paraxostylar granules which have varied shape and inhomogeneous content with frequent myelin figures, indicating a digestive function. The rest of the phosphatase and most of the acid beta-glucuronidase activity are in a smaller granule fraction with an equilibrium density around 1.18. The latency of these enzymes is quite resistant to freezing and thawing. This particle population consists of smaller, very often flattened vesicles and granules, many of which are clearly fragments of the prominent Golgi apparatus of the cell.
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PMID:Biochemical cytology of trichomonad flagellates. I. Subcellular localization of hydrolases, dehydrogenases, and catalase in Tritrichomonas foetus. 414 6

The series introduced by this paper reports the results of a detailed analysis of the microsomal fraction from rat liver by density gradient centrifugation. The biochemical methods used throughout this work for the determination of monoamine oxidase, NADH cytochrome c reductase, NADPH cytochrome c reductase, cytochrome oxidase, catalase, aminopyrine demethylase, cytochromes b(5) and P 450, glucuronyltransferase, galactosyltransferase, esterase, alkaline and acid phosphatases, 5'-nucleotidase, glucose 6-phosphatase, alkaline phosphodiesterase I, N-acetyl-beta-glucosaminidase, beta-glucuronidase, nucleoside diphosphatase, aldolase, fumarase, glutamine synthetase, protein, phospholipid, cholesterol, and RNA are described and justified when necessary.
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PMID:Analytical study of microsomes and isolated subcellular membranes from rat liver. I. Biochemical methods. 415 Apr 88

Rat liver microsomal fractions have been equilibrated in various types of linear density gradients. 15 fractions were collected and assayed for 27 constituents. As a result of this analysis microsomal constituents have been classified, in the order of increasing median density, into four groups labeled a, b, c, and d. Group a includes: monoamine oxidase, galactosyltransferase, 5'-nucleotidase, alkaline phosphodiesterase I, alkaline phosphatase, and cholesterol; group b: NADH cytochrome c reductase, NADPH cytochrome c reductase, aminopyrine demethylase, cytochrome b(5), and cytochrome P 450; group c: glucose 6-phosphatase, nucleoside diphosphatase, esterase, beta-glucuronidase, and glucuronyltransferase; group d: RNA, membrane-bound ribosomes, and some enzymes probably adsorbed on ribosomes: fumarase, aldolase, and glutamine synthetase. Analysis of the microsomal fraction by differential centrifugation in density gradient has further dissociated group a into constituents which sediment more slowly (monoamine oxidase and galactosyltransferase) than those of groups b and c, and 5'-nucleotidase, alkaline phosphodiesterase I, alkaline phosphatase, and the bulk of cholesterol which sediment more rapidly (group a2). The microsomal monoamine oxidase is attributed, at least partially, to detached fragments of external mitochondrial membrane. Galactosyltransferase belongs to the Golgi complex. Group a2 constituents are related to plasma membranes. Constituents of groups b and c and RNA belong to microsomal vesicles derived from the endoplasmic reticulum. These latter exhibit a noticeable biochemical heterogeneity and represent at the most 80% of microsomal protein, the rest being accounted for by particles bearing the constituents of groups a and some contaminating mitochondria, lysosomes, and peroxisomes. Attention is called to the operational meaning of microsomal subfractions and to their cytological complexity.
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PMID:Analytical study of microsomes and isolated subcellular membranes from rat liver. 3. Subfractionation of the microsomal fraction by isopycnic and differential centrifugation in density gradients. 415 Apr 90

Isopycnic equilibration and sedimentation rate studies of rat liver microsomes led previously to the assignment of microsomal constituents into group a1 (monoamine oxidase), group a2 (5'-nucleotidase, alkaline phosphodiesterase I, alkaline phosphatase and cholesterol), group a3 (galactosyltransferase), group b (NADH cytochrome c reductase, NADPH cytochrome c reductase, aminopyrine demethylase, cytochrome b(5) and P 450), and group c (glucose 6-phosphatase, esterase, nucleoside diphosphatase, beta-glucuronidase and glucuronyltransferase). Confirmation and extension of the assignment into groups has been obtained by studying the differential effect of the reagents digitonin, EDTA, and PPi. Digitonin specifically affected the equilibrium density only of the group a2 and (to a lesser extent) group a3, and not of groups b and c under conditions which preserved the structure-linked latency of nucleoside diphosphatase and galactosyltransferase. Within experimental error the rate of sedimentation of all microsomal constituents was unaffected. The morphological appearance under the electron microscope was indistinguishable from that of nondigitonin-treated microsomes, except that a few smooth membranes (< 10%) exhibited broken-looking profiles. Treatment of microsomes with EDTA or PPi detached a substantial part of RNA and released protein in excess over the amount accountable for by detachment of ribosome constituents. This detachment was confirmed by electron microscopy. EDTA and PPi decreased markedly the equilibrium density and the density dispersion of groups b and c, due mainly to the uncoating of rough elements. EDTA and PPi shifted slightly the distribution profiles of groups a towards lower densities, possibly as a result of the release of adsorbed proteins. The combination of EDTA and digitonin, used subsequently, rendered the average equilibrium density of group a2 higher than that of groups b and c. Dense subfractions were thus enriched in constituents of group a2 and showed mainly broken-looking vesicles under the electron microscope. The import of our results on the biochemical and enzymic properties of the subcellular components of the microsome fractions is discussed.
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PMID:Analytical study of microsomes and isolated subcellular membranes from rat liver. IV. Biochemical, physical, and morphological modifications of microsomal components induced by digitonin, EDTA, and pyrophosphate. 436 10


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