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At least 937 records · Page 52Linked to original sources
PubMed1981

Fluoride resistant alpha-naphthyl acetate esterase and combined enzyme histochemistry in the study of normal and pathologic lymphoid tissues.

Alpha-Naphthyl acetate esterase (ANAE) and fluoride resistant alpha-naphthyl acetate esterase (FRANAE) have been compared as histochemical methods to identify T lymphocytes in sections of normal and pathological human lymphoid tissues. In addition, the FRANAE method was combined with alkaline phosphatase (ALP) in order to simultaneously evaluate the relationship between T lymphocytes and fibroblastic reticular cells (ALP) positive). The "dot like" esterase positivity of T lymphocyte was better evaluated by using FRANAE when compared to ANAE because of fluoride inhibitor of the strong esterase activity of dendritic cells and most macrophages. The combined ALP-FRANAE method clearly demonstrated a large number of fibroblastic reticular cells within the T-areas in various normal and pathological tissues such as hyperplastic lymph nodes and especially in the lymph nodes and spleens from patients with Hodgkin's disease.

Alkaline Phosphatase↗
PubMed1982

[Rapid method for the identification of esterase-positive cells in suspensions of mononuclear cells separated by a Ficoll-Paque gradient].

Cytochemical staining for acid alpha-naphthyl acetate esterase (ANAE) activity is widely used for identifying monocytes in mixed cell populations; esterase staining is usually performed on slide prepartions of whole blood, buffy coat or Ficoll-Paque separated mononuclear cells (MC). In this paper we propose a method for staining MC while they are in suspension, which utilizes, with slight modifications, the same reagents used in the procedure for esterase staining on smears. Suspension method is rapid and costless; furthermore, it overcomes the loss of esterase stainability observed in slide preparations of Ficoll-Paque separated MC.U

Carboxylic Ester Hydrolases↗
PubMed1981

The activity of alkaline and acid phosphatase and non-specific esterase in experimental bovine cysticercosis at different stages of development.

The activity of alkaline and acid phosphatase and non-specific esterase was detected both in the parasite and in the tissue reaction on days 21, 23, 42, 168 and 261 after experimental infection. A very high activity of all enzymes was found in 21- and 23-day-old C. bovis in the tegument of whole bladder. In 42, 168 and 261 days old cysticerci the activity of alkaline acid phosphatase was limited only to a part of bladder surrounding the opening of the spinal canal, whereas the activity of non-specific esterase was present in the whole bladder. The activity of non-specific esterase was localized in subtegumental cells of the bladder wall and in small bodies in the bladder and scolex. These bodies increased in number with the age of the cysticercus. In the tissue reaction, a high activity of alkaline phosphatase was detected only in the period of about 20 days after infection in the layer of activated fibroblasts. The activity of acid phosphatase was demonstrated in the tissue reaction in all time periods and was localized in the histiocytes, macrophages, necrotic exudate, necrotic foci and pigment cells at the periphery of tissue reaction. These cells exhibited also the activity of non-specific esterase.

Acid Phosphatase↗
PubMed1995

[Preparation and characterization of monoclonal antibodies against esterase of malathion-resistant Culex quinquefasciatus].

Five clones of monoclonal antibodies (McAbs) were generated from BALB/c mice which were activized with PPD and immunized with esterases extracted from malathion-resistant Culex quinquefasciatus. All 5 clones of McAbs belonged to the IgG1 subtype, additive index (A.I.) of every two McAbs did not exceeded 50%. After a 1 h of incubation, the McAbs at the titer of 1:1,000 completely inhibited the activity of the amplified esterases. Of 8 strains of adult mosquitoes studied by Western-blot assay, all exhibited the 64 kDa esterase band recognized by the McAbs, six (SP, FS, SH, CD, RD, RM) showed more bands of different MW (43-60 kDa), the higher the organophosphorus resistant level, the more and the denser the bands. The above McAbs had little or no effect against the esterases of dimethrin-resistant strain and the larva stage of malathion-resistant Culex quinquefasciatus.

Animals↗
PubMed1975

A comparative histochemical study of the distribution of esterase in the gastro-intestinal tract of some Indian teleosts.

The investigations on the distribution of esterase (EC 3.1.1.1) activity in the gastro-intestinal tract of four Indian fresh water teleost fishes, namely Mastacembelus, Bagarius, Glossogobius and Rohtee showed that the highest esterase activity occurred in the case of Mastacembelus. No notable esterase activity was recorded in the stomach of Bagarius and Glossogobius and in the intestinal bulb of Rohtee. The distribution of the esterase activity in the tissues of the intestine of all the fishes studied suggests the clue for the production of the enzyme in the intestine of the fishes as well. The sites of the distribution of the enzyme through the gastro-intestinal tract of the four fishes have been discussed.

Animals↗
PubMed1996

Release of ferulic acid from sugar-beet pulp by using arabinanase, arabinofuranosidase and an esterase from Aspergillus niger.

Aspergillus niger cinnamoyl esterase (CinnAE) is shown to be active towards a wide range of feruloylated oligosaccharides derived from sugar-beet pulp (SBP). The esterase hydrolysed ferulic acid ester-linked to either C-2 of arabinose or C-6 of galactose residues, and demonstrated the highest activity towards the feruloylated arabinose trisaccharide. However, CinnAE was able to release only 0.88% of total alkali-extractable ferulic acid from SBP in 24 h when acting alone. To determine whether cell-wall-degrading enzymes could increase the release of ferulic acid by CinnAE, SBP was incubated with various carbohydrases [cellulase, polygalacturonase, endo-arabinanase, alpha-L-arabinofuranosidase, endo-(1,4-beta-D-galactanase, beta-D-galactosidase]. These were added alone and in pairs, both in the presence and absence of CinnAE. We showed that all the carbohydrases tested were free of esterase activity. When individual carbohydrases were incubated with SBP, whether in the presence or absence of CinnAE, less than 1% of the feruloyl groups were released. When incubated with a mixture of endo-arabinanase and alpha-L-arabinofuranosidase, the esterase was able to release 14 times more of the alkali-extractable ferulic acid present in the whole pulp as free acid than CinnAE alone. Ferulic acid is linked either to L-arabinose or D-galactose in SBP, but no corresponding increase in ferulic acid release was detected when SBP was incubated with CinnAE plus endo-(1,4)-beta-D-galactanase and beta-D-galactosidase (both from A. niger). Hence feruloylated arabinans in SBP are readily available for hydrolysis by arabinan-degrading enzymes, whereas feruloylated galactans are not available for hydrolysis by galactan-degrading enzymes.

Aspergillus niger↗
PubMed1977

[Esterase spectrum in the hepatocytes and Kupffer cells of regenerating liver].

The esterase spectra of hepatocytes and Kupffer's cells from the regenerating rat liver were studied following partial hepatectomy. The starch-gen electrophoresis method was used. The relative number of Kupffer's cells, per cent of phagocytising Kupffer's cells, as well as mitotic rate of hepatocytes were determined. Hepatocyte esterase spectra from the intact liver consisted of six, whereas that of Kupffer's cells--of five zones of the enzyme activity. A "simplification" of hepatocyte esterase spectra could be seen 2 1/2 hours after partial hepatectomy. Additional activity bands appeared in 9 hours; these could be identified for a period of up to 24 hours after the operation. The initiar esterase spectrum was regained within 48 hours. The same tendency was observed in Kupffer's cells, but no full restoration of the enzyme spectra was observed 72 hours after partial hepatectomy.

Animals↗
PubMed1977

[Expression of genes controlling esterases during the embryonic development of hybrid fish].

The electrophoretic mobility of several enzymes was studied in the embryos and early larvae of the hybrids between the loach (Misgurnus fossilis) and the aquarial cyprinids and cobitids (Acanthophthalmus). The cytosol aspartate aminotransferase is represented by one protein with the same mobility at all developmental stages both in the loach and in the hybrids. Malate dehydrogenase manifests four bands of isozymes which suffer no changes during the development. The electrophoretic profile of lactate dehydrogenase remains constant (10 isozymes) until hatching, but only 5 isozymes are found in the 5 days old larvae. Similar changes occur in the Misgurnus X Acanthophthalmus hybrids. The nonspecific esterases are represented by several proteins with different activities; their number increases after hatching. In the oocytes and adult specimens of Acanthophthalmus a characteristic and very active esterase was found which is absent in the loach. In the Misgurnus X Acanthophthalmus hybrids this esterase appears prior to the hatching and its activity later increases. Thus, the expression of the gene of one esterase begins in the end of embryogenesis.

Animals↗
PubMed1996

Biology of Amazonian anopheline. XX. Ontogeny of esterases, leucine aminopeptidase and alpha-glycerophosphate dehydrogenase in Anopheles (Nyssorhynchus) darlingi Root, 1926 (Diptera, Culicidae).

The esterases, leucine aminopeptidase and alpha-glycerophosphate dehydrogenase revealed modifications in gene expressions during the development of Anopheles darlingi. The esterases showed five activity bands, 1 and 2 being more deeply stained during the larval stages than in pupae or adults, esterases 3 and 4 more deeply stained in pupae and adults whereas esterase 5 was present throughout development. Leucine aminopeptidase showed five activity bands: LAP2 and LAP5 were characteristic of larvae, LAP3 was specific for pupae and adults, LAP4 was detected only in pupae, and LAP1 and LAP6 were detected in all stages. alpha-Glycerophosphate dehydrogenase presented one activity band on starch gel whose intensity increased with development. Two activity bands were detected on polyacrylamide gel (alpha-GPDH1 and alpha-GPDH2) in 4th-instar larvae (old pigmented larvae) and this activity increased with development.

Animals↗
PubMed1998

Interaction of Triton X-100 with acyl pocket of butyrylcholinesterase: effect on esterase activity and inhibitor sensitivity of the enzyme.

The effect of non-ionic detergents like Triton X-100, Lubrol PX, Brij 35 and Tween 80 on the esterase activity and inhibitor sensitivity of human serum butyrylcholinesterase (BuChE) were studied. The results showed that though BuChE is not a detergent dependent enzyme, the esterase activity and inhibitor sensitivity of it can be modulated by the presence of detergents. All the detergents caused a marginal activation of the esterase activity. The presence of Lubrol PX, Brij 35 or Tween 80 did not affect the 50% molar inhibition concentration (IC50) of the inhibitors tested. But in the presence of Triton X-100 the IC50 values were increased for neostigmine, eserine and tetraisopropylpyrophosphoramide (acylation site interacting inhibitors), whereas for inhibitors like ethopropazine, imipramine and procainamide (choline binding pocket specific inhibitors) the IC50 values were unaltered. In addition, in the presence of Triton X-100 the bimolecular reaction constant for phosphorylation reaction (ki) of BuChE for the acyl pocket specific tetraisopropylpyrophosphoramide was reduced. Triton X-100 partially protected BuChE against this tetraisopropylpyrophosphoramide inactivation. These results indicate that Triton X-100 by interacting with the acyl pocket hydrophobic region is able to activate the esterase activity of BuChE. Further it reduces the capacity of the enzyme to react with inhibitors that inactivate it by interacting with the serine residue of the acylation site.

Butyrylcholinesterase↗
PubMed1991

Determination of rat plasma esterase-1 (ES-1) activity by scanning densitometry of gradient polyacrylamide gels with zymogram detection.

There is no specific assay for rat plasma esterase-1 (ES-1) activity. Plasma contains many esterases, while known substrates do not discriminate between esterases. With gel electrophoresis, plasma esterase isozymes can be separated. Thus, a method consisting of gradient polyacrylamide gel electrophoresis, visualization of the enzyme with a staining technique based on substrate conversion, and densitometric scanning of the stained gel has been developed for quantitative measurement of rat plasma ES-1 activity. ES-1 activities were expressed as total peak areas. Reproducibility of the method was found to be about 10% (expressed as apparent between-gel coefficient of variation). When the ES-1 zone areas was expressed relative to that of a plasma ES-1 standard, reproducibility was about 3%. The kinetics of catalysis of alpha-naphthyl acetate hydrolysis by ES-1 could be determined with the gel scanning assay; the Km was 0.76 mM. At the alpha-naphthyl acetate concentration of 2.69 mM, total peak areas of the ES-1 zone were linearly associated with the staining time (up to at least 40 min) and amount of plasma (up to 26.25 microL). The pH of the staining buffer influences the ES-1 zone area, the largest areas being obtained when the pH ranged between 7.0 and 7.8. With propionate as acyl moiety of the alpha-naphthyl ester substrate, ES-1 zone areas were higher than with either acetate, butyrate or hexanoate.

Animals↗
PubMed1983

The cloning and expression of the gene encoding organ-specific esterase S from the genome of Drosophila virilis.

We have cloned the gene for the esterase S isozymes complex from the genome of Drosophila virilis in pBR322. Esterase S is an enzyme which is specifically synthesized in the ejaculatory bulbs of D. virilis adult males. The gene for the esterase S isozyme complex (estS) has been localized in band 2G5e of chromosome II. Poly(A)+ RNA prepared from ejaculatory bulbs actively hybridizes with this band. A cloned 15-kb fragment of D. virilis DNA (pVE9) also hybridizes with band 2G5e. The area encoding the poly(A)+ RNA is located in the middle part of the cloned fragment whose ends are not transcribed in vivo. Only one poly(A)+ RNA which is 1.9 kb long and complementary to pVE9 DNA can be revealed in the cytoplasm. The mRNA preselected by hybridization to pVE9 DNA was microinjected into the cytoplasm of Xenopus laevis oocytes. In other experiments, the pVE9 DNA itself was microinjected into oocyte nuclei. In both cases, esterase S is synthesized in the oocytes, and the major part of the protein is transported from the oocytes and accumulated in the incubation medium.

Animals↗
PubMed1987

Radioimmunoassay in blood plasma of arginine esterase: the major secretory product of dog prostate.

We have developed a radioimmunoassay to determine serum levels of arginine esterase, the major secretory product of the canine prostate. Although the antibodies recognized other related proteins in immunoblotting conditions, particularly in the pancreas, the radioimmunoassay appeared specific for arginine esterase of prostatic origin and reacted only slightly or not at all with cytosolic proteins from salivary glands, liver, skeletal muscles, and kidney. In serum samples, the sensitivity limit of the assay was about 2.5 ng per ml. The interassay and intraassay variations for serum samples that contained concentrations of arginine esterase ranging from 6 to 21 ng per ml were, respectively, 14% and 24%. Sera from 30 adult males and 14 adult females contained, respectively, 71 +/- 9 and 5.3 +/- 0.4 ng per ml. In a group of 12 dogs treated daily for 36-39 days with 50 micrograms of D-Trp6-luteinizing hormone-releasing hormone ethylamide, the concentrations of arginine esterase in the serum decreased progressively and became identical with those observed in the females. These results constitute the first evidence for the presence of a serum marker of the normal prostate in an experimental model. It should be particularly useful to test the effects of various agents on the prostate.

Animals↗
PubMed1993

Characterization of rat plasma esterase ES-1A concerning its molecular and catalytic properties.

To characterize esterase ES-1A from rat plasma with regard to its molecular and catalytic properties, the enzyme was purified. The degree of purification, as measured by a densitometric gel scanning assay for ES-1 activity, was about 142-fold with a recovery of 9%. The ES-1A preparation was free of other plasma esterases but not of other plasma proteins. The enzyme shows microheterogeneity after staining for esterase activity in gradient polyacrylamide gel electrophoresis and isoelectric focusing. The native ES-1A protein is a carboxylesterase (EC 3.1.1.1) with a molecular mass of about 59 kDa as determined by gel filtration and gradient polyacrylamide gel electrophoresis. ES-1A exhibits a pI of 4.73 and optimum pH of 8.6 for p-nitrophenylbutyrate hydrolysis. With various p-nitrophenyl esters as substrate for ES-1A, it was found that the Michaelis constant decreased with increasing number of C atoms of the unbranched fatty acid moiety, whereas the maximum reaction velocity peaked with p-nitrophenylvalerate. The high degree of similarity of the properties of rat ES-1A with those reported earlier for mouse ES-2B, rabbit EST-2F, and human ESB2 suggests that these four esterases have a common evolutionary origin.

Animals↗
PubMed1998

Butyrivibrio spp. and other xylanolytic microorganisms from the rumen have cinnamoyl esterase activity.

High concentrations of hydroxycinnamic acids in the hemicellulosic fraction of dry season tropical grasses may influence the rate of microbial degradation of arabinoxylans by ruminant animals. The ability of 22 strains of Butyrivibrio fibrisolvens, other ruminal bacteria (Ruminococcus albus SY3, Ruminococcus flavefaciens RF1,Prevotella ruminicola AR20) and the ruminal phycomycete Neocallimastix patriciarum CX to digest the tropical grass Heteropogon contortus(spear grass) and hydrolyse esterified ferulic and p-coumaric acid was examined. Significant digestion (8-36%) of spear grass occurred with the B. fibrisolvens strains H17c, A38, LP92-1-1, 49,R. albus SY3 and N. patriciarum. Hydrolysis of ester-linked ferulic and p-coumaric acid occurred with all organisms except B. fibrisolvens strains GS113, OB156 and LP1028 and P. ruminicola AR20. The ratio of ferulic to p-coumaric acid hydrolysed by different strains of Butyrivibrio spp. varied markedly from 0.96 for AR 51 to 0.16 for A38. Butyrivibrios which were fibrolytic (H17c and A38) had higher extracellular cinnamoyl esterase activity than bacteria that did not digest spear grass fibre (LP 91-4-1 and AR 20) which had low activities or only produced cell associated enzyme. Cell associated and extracellular esterase activity were induced when Butyrivibrio spp. strains H17c, A38 and E14 and the Ruminococcus spp. were grown on birchwood xylan but induction did not occur to the same extent with N. patriciarum. This is the first reported observation of cinnamoyl esterase activity in the genus Ruminococcus. The fungus N. patriciarum had significantly higher digestibility of spear grass and solubilisation of phenolic acids than the bacteria. The study shows that high levels of extracellular cinnamoyl esterases are characteristic of a selection of fibre-degrading ruminal bacteria and fungi which probably indicates that these enzymes are common amongst xylanolytic ruminal microorganisms.

Journal Article↗
PubMed1993

Linkage studies of the esterase D and retinoblastoma genes to canine copper toxicosis: a model for Wilson disease.

Canine copper toxicosis, an autosomal recessive disorder, is prevalent among certain dog breeds. It results in liver disease from copper accumulation and toxicity similar to the human autosomal recessive disorder, Wilson disease. The Wilson disease locus has been mapped to 13q and is closely linked to the esterase D and retinoblastoma genes. We developed informative polymorphic systems in the dog using the human cDNA clones of the esterase D and retinoblastoma loci as probes. We investigated the linkage relationship of these two loci to the copper toxicosis locus, and to each other in the dog. Our results indicate that none of the loci are closely linked in the dog. Linkage of copper toxicosis to the retinoblastoma locus can be excluded up to 13% recombination, and to esterase D up to 5% recombination. Furthermore, esterase D and retinoblastoma, tightly linked in the mouse and human genomes, are not found to be closely linked in the canine genome.

Animals↗
PubMed1996

Interspecies variation of "B" esterases in birds: the influence of size and feeding habits.

Interspecies differences in "B" esterases were evaluated in seven species of wild birds in order to investigate their different susceptibilities to organophosphorus (OP) insecticides. The relationship between "B" esterases and body size and the influence of feeding habits in the evolution of esterase activities were explored. An in vitro inhibition test was carried out with paraoxon and azinphos methyl oxon in order to investigate the role of equilibrium binding parameters (acetylcholinesterase/ organophosphorus compounds affinity) in determining susceptibility of the different species to parathion and azinphos methyl. Esterase activities were different in all species. The smallest bird studied (the sparrow) had the highest brain acetylcholinesterase (AChE) and plasma carboxylesterase (CbE) activities. The largest bird (the cormorant) had the lowest level of both activities. For microsomal CbE, the coot had the highest activity. An inverse correlation was found between brain AChE and plasma CbE activity in relation to body size. Omnivorous species showed the highest brain AChE and plasma CbE activities which were low in species with a specialised diet. The in vitro inhibition test demonstrated the active involvement of equilibrium binding parameters in determining different susceptibilities to these contaminants in birds.

Acetylcholinesterase↗
PubMed1984

Genetic analysis of human lymphocyte proteins by two-dimensional gel electrophoresis: VI. Identification of esterase D in the two-dimensional gel electrophoresis pattern of cellular proteins.

C33k polypeptide, which is a cytosol polypeptide with molecular weight of 33 000 and approximate pI value of 7.5, has three common electrophoretic phenotypes and is an abundant polypeptide in peripheral blood lymphocytes, fibroblasts and red blood cells. Family and population studies indicate that the three phenotypes of C33k polypeptide are determined by two common alleles at a single autosomal locus. The gene frequencies of the two common alleles were 0.642 and 0.358, respectively, in a Japanese population. Since esterase D has a subunit size and gene frequencies similar to those of C33k polypeptide, the phenotypes of C33k polypeptide and esterase D were compared in 18 families totaling 72 members. Perfect concordance of the phenotypes between C33k polypeptide and esterase D was observed in all 72 members. In addition, a gene dosage effect on the expression of the phenotype of C33k polypeptide was observed in the red blood cell lysate from a patient with partial 13q trisomy who was reported to have two doses of EsD1 and one dose of EsD2. These data indicate that the polymorphic C33k polypeptide is esterase D, which is assigned to chromosome 13q14. This finding is useful for the detection of proteins coding for by chromosome 13q14-linked genes in the studies on human gene mapping using somatic hybrid cell lines and two-D gel electrophoresis.

Blood Proteins↗