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PubMed1981

Purification and characterization of esterase 1F, the albumin esterase of the house mouse (Mus musculus).

Esterase 1F was isolated from mouse serum and purified by ion-exchange chromatography, isoelectrofocusing, and molecular sieve chromatography. It is considered to be a glycoprotein with an apparent molecular weight of 75 000. The equivalent weight (approximately equal to 77 000 X g/mol) was estimated by titration of the catalytic site with diethyl p-nitrophenyl phosphate. The Michaelis constant Km and the catalytic constant kcat of the enzyme for 4-nitrophenyl hexanoate were determined. Esterase 1F is characterized by its ability to split a wide spectrum of substrates and its relatively low turnover rates towards the substrates tested. It belongs to the isozyme system of carboxylesterase (EC 3.1.1.1) coded for by chromosome 8. Esterase 1F was compared with three other genetically related isozymes, esterase 2, esterase 7 and esterase 9, with respect to some physical and catalytic properties.

Animals↗
PubMed1978

Genetics of esterases in Drosophila. VI. Gene system regulating the phenotypic expression of the organ-specific esterase in Drosophila virilis.

It is shown that the gene controlling the synthesis of the organ-specific S-esterase of Drosophila virilis ejaculatory bulbs is located on the second chromosome (at approximate position 192.1 +/- map units). The cells of the genital imaginal disks are determined for the synthesis of S-esterase 10-12 hr after the second molt. The organ-specific esterase can be detected after adult emergence only. It is preceded by an increase in RNA content and by enhancement of RNA synthesis in the cells of the ejaculatory bulbs. Interstock differences were found in the level of the activity of S-esterase, which is under the control of the X chromosome, as well as in the time of expression of enzyme activity, which is controlled by the fifth chromosome. It is suggested that the specific phenotypic expression of this enzyme depends on the system of genes with regulatory expression at both the transcriptional and posttranscriptional levels. The genetic control of the synthesis of the S-esterase described is a convenient model for studying mechanisms of gene activity regulation in eukaryotes.

Animals↗
PubMed1994

A cluster of esterase genes on chromosome 3R of Drosophila melanogaster includes homologues of esterase genes conferring insecticide resistance in Lucilia cuprina.

We identify an esterase isozyme in Drosophila melanogaster, EST 23, which shares biochemical, physiological, and genetic properties with esterase E3, which is involved in resistance to organophosphate insecticides in Lucilia cuprina. Like E3, the D. melanogaster EST 23 is a membrane-bound alpha-esterase which migrates slowly toward the anode at pH 6.8. Both enzymes have similar preferences for substrates with shorter acid side chain lengths. Furthermore, on the basis of their high sensitivity to inhibition by paraoxon and their insensitivity to inhibition by eserine sulfate, both enzymes were classified as subclass I carboxylesterases. The activity of each enzyme peaks early in development and, again, in the adult stage. Both enzymes are found in the male reproductive system and larval and adult digestive tissues, the latter being consistent with a role for these enzymes in organophosphate resistance. Fine structure deficiency mapping localized Est 23 to cytological region 84D3 to E1-2 on the right arm of chromosome 3. Moreover, we show that the genes encoding three other esterase phenotypes also map to the same region; these phenotypes involve allozymic differences in EST 9 (formerly EST C), ali-esterase activity, defined by the hydrolysis of methyl butyrate, and malathion carboxylesterase activity, defined by hydrolysis of the organophosphate malathion. This cluster corresponds closely to that encompassing E3 and malathion carboxylesterase on chromosome 4 in L. cuprina, the homologue of chromosome 3R in D. melanogaster.

Animals↗
PubMed1995

Serine esterase (BLT-esterase) activity in murine splenocytes is increased with exercise but not training.

The effect of a treadmill exercise bout (30 m/min, 4 degrees slope, 30 min) or 9 weeks of training (18 m/min, 0 degrees slope, 45 min/day, 5 x/week) on splenic natural killer cell activity (NKCA) and BLT-esterase activity was studied in adult C3/He male mice. These immune parameters were assessed in mice who had been injected i.p. 24 h before sacrifice with saline or poly I:C, an interferon inducer and activator of killer cells in vivo. Acutely exercised mice pretreated with saline had an increase in NKCA and BLT-esterase activity 5 minutes after cessation of exercise relative to values at rest. The frequency of asialo GM1 positive splenocytes did not differ in the saline injected, acutely exercised mice compared to values obtained before exercise. Animals pretreated with poly I:C did not differ in their NKCA or BLT-esterase activity as a function of time. Trained mice injected with saline had a significant increase in the in vitro splenic NKCA and in the frequency of splenocytes positive for asialo GM1 compared with sedentary controls. However, BLT-esterase activities did not differ by training status. Pretreatment with poly I:C augmented NKCA in all groups of mice and abolished the significant effects observed with acute exercise or training on fresh natural killer cells. These results indicate that the increase in splenic natural killer cell activity immediately after acute exercise is accompanied by an increase in the activity of the granule lytic enzyme, BLT-esterase, presumably involved in delivery of the 'lethal hit'.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

Esterase-29 (ES-29): biochemical characterization and control by two independent gene loci of a testosterone-dependent mouse serum esterase.

Biochemistry and genetics of a testosterone-dependent murine serum esterase designated esterase-29 (ES-29) are described. The enzyme was identified after disc electrophoresis and subsequent staining for esterase using alpha-naphthyl acetate as the substrate. It was inhibited by bis-p-nitrophenyl phosphate and was resistant to p-chlorophenylsulphonate and hence was classified as carboxylesterase EC3.1.1.1. The molecular mass was estimated to be about 130 kDa. It was shown that ES-29 is under the control of two independent genes. The first, termed Es-29, is suggested to be a structural locus, linked to the cluster-2 esterase loci on chromosome 8. Three alleles at Es-29, Es-29a, Es-29b, and Es-29c are distinguished, which determine absence (SEG/1), strong activity (BALB/cJ), and low activity (MOLH/Fre), respectively. The second locus, termed Mse-1 (serum esterase modifying factor), was found to be closely linked to Pre-2 on chromosome 12 and is suggested to be a modifying or regulatory gene. Two alleles were distinguished, Mse-1a (BALB/cJ) and Mse-1m (MOL3/JA, Cas-Bgr), which determine whether ES-29 appears as a single band or a double band, respectively. Mse-1m is dominant to Mse-1a.

Animals↗
PubMed1979

Endplates after esterase inactivation in vivo: correlation between esterase concentration, functional response and fine structure.

Mouse sternomastoid muscles were incubated with diisopropylfluorophosphate (DFP) in vivo, and the time course of recovery was studied using histochemistry, EM autoradiography and physiology. We found that: (1) the ability of the muscle to sustain tetanus in response to nerve stimulation is eliminated when the esterases at the neuromuscular junctions are saturated with DFP. This ability is regained partially when less than 10% of the DFP-binding sites have recovered. (2) There is a positive correlation between the frequency of stimulation at which the tetanic response can be maintained and the extent of acetylcholinesterase (AChE) recovery. (3) Tetanic responses at fusion frequency (about 100 Hz) appear indistinguishable from controls with only about 25% of normal AChE. (4) Butyrylcholinesterase (BuChE) possibly of Schwann cell origin recovers more rapidly than does AChE. (5) The muscle shows fine structural changes involving Z band dissolution and the breakdown of sarcoplasmic reticulum within hours after esterase inactivation. (6) This myopathy reaches a peak at three days after esterase inactivation and is almost fully recovered by two weeks. (7) It can be eliminated if, at the time of esterase inactivation, the nerve is cut or the acetylcholine receptors at the endplate are inactivated by alpha-bungarotoxin. We suggest that the myopathy, seen after DFP, is mediated by Ca2+ fluxes due to prolonged action of acetylcholine (ACh) in the absence of esterases.

Acetylcholinesterase↗
PubMed1976

Esterase. XXII. Cellular and subcellular localisation of the Es-9 esterase in mouse kidney.

Among the various esterases of the mouse kidney the Es-9 esterase is outstanding in that it is fully repressed in the cortical proximal tubulus in the absence of testosterone but is constitutive in the terminal parts of the proximal tubulus. Thus, this enzyme is regulated in a different way in closely neighboured sections of the tubular system. Comparing the disc electrophoretic patterns of the kidney esterases with the distribution of esterases in ultrathin sections as revealed by electron microscopy it is concluded that the Es-9 esterase is located in the mitochondria.

Animals↗
PubMed2004

The crystal structure of feruloyl esterase A from Aspergillus niger suggests evolutive functional convergence in feruloyl esterase family.

As a component of the array of enzymes produced by micro-organisms to deconstruct plant cell walls, feruloyl esterases hydrolyze phenolic groups involved in the cross-linking of arabinoxylan to other polymeric structures. This is important for opening the cell wall structure, making material more accessible to glycosyl hydrolases. Here, we describe the first crystal structure of the non-modular type-A feruloyl esterase from Aspergillus niger (AnFaeA) solved at 2.5A resolution. AnFaeA displays an alpha/beta hydrolase fold similar to that found in fungal lipases and different from that reported for other feruloyl esterases. Crystallographic and site-directed mutagenesis studies allow us to identify the catalytic triad (Ser133-His247-Asp194) that forms the catalytic machinery of this enzyme. The active-site cavity is confined by a lid (residues 68-80), on the analogy of lipases, and by a loop (residues 226-244) that confers plasticity to the substrate-binding site. The lid presents a high ratio of polar residues, which in addition to a unique N-glycosylation site stabilises the lid in an open conformation, conferring the esterase character to this enzyme. A putative model for bound 5,5'-diferulic acid-linked arabinoxylan has been built, pointing to the more relevant residues involved in substrate recognition. Comparison with structurally related lipases reveals that subtle amino acid and conformational changes within a highly conserved protein fold may produce protein variants endowed with new enzymatic properties, while comparison with functionally related proteins points to a functional convergence after evolutionary divergence within the feruloyl esterases family.

Aspergillus niger↗
PubMed1987

Distinction between 'A'-esterases and arylesterases. Implications for esterase classification.

'A'-esterase activities (substrates paraoxon and pirimiphos-methyloxon) and arylesterase activities (substrate phenyl acetate) were assayed in the sera of 14 species of birds representing seven different orders and 11 species of mammal representing five different orders. Ten species of birds had no detectable 'A'-esterase, and the remaining four species only low activity, yet all birds showed considerable arylesterase activity (16.8-99.3 mumol/min per ml of serum). Ten species of mammal showed both 'A'- and 'aryl'-esterase activities. In humans, gel filtration of serum completely separated peaks representing paraoxonase and arylesterase activities. Thus, in both birds and humans, serum enzymes exist that express arylesterase activity but not 'A'-esterase activity. These findings suggest that a distinction should be made between these two types of esterase in future classifications.

Animals↗
PubMed1982

Purification and characterization of esterase 6A, a trimeric esterase of the house mouse (Mus musculus).

Esterase 6A was isolated from mouse lung and purified 440-fold by ion-exchange chromatography, inverse ammonium sulphate gradient solubilization, gel filtration and isoelectric focusing. The resultant product was apparently homogenous by the criteria of polyacrylamide gel electrophoresis and immunodiffusion, and consisted of the electrophoretic form 6A3. A single species of subunit was present on sodium dodecyl sulphate gel electrophoresis. The molecular weight of the native protein was found to be about 178,000 with a subunit molecular weight of about 60,000. The equivalent weight obtained by active-site titration with diethyl-p-nitrophenyl phosphate was approximately 178,000 g/mol, indicating a functional asymmetry in the trimer. The enzyme was shown to have a high affinity for 4-nitrophenyl hexanoate (Michaelis constant Km = 4.4 mumol/l) with a relatively low catalytic efficiency (catalytic constant kcat = 12 s-1). Esterase 6A was immunologically related to esterase 1 and esterase 9, with which it is genetically closely linked. Further properties of the three esterases were compared.

Animals↗
PubMed1977

[Nonspecific esterase and naphthol-AS-D-chloroacetate esterase in monocytoid and myeloid cells of healthy cattle and cattle suffering from leukosis].

The reaction to non-specific esterase can be used for the identification of the monocytoid cells of the periphery. A negative reaction is exhibited by neutrophile and eosinophile leucocytes and erythrocytes. Varying results are obtained from lymphocytes, rendering it impossible to use this method in the group of lymphoid cells of the periphery or marrow. In the group of large marrow cells (promonocytes), non-specific esterase gave a very strong reaction; this applies both to the marrow of healthy cattle and cattle suffering from leucosis. For the time being, efforts to use this reaction for the solution of the problem of the differentiation of monocytoid cells and cells of similar size in the myeloid series of the bone marrow have not been successful. In neutrophile leucocytes of the periphery, naphtol-AS-D-chloroacetate esterase gives a less intensive reaction than in humans. For this reason, it is less suitable for the differentiation of these cells. Other cell types (eosinophile leucocytes, monocytes, lymphocytes, erythrocytes as well as their bone-marrow stages) give a negative reaction. In the group of large marrow cells of the myeloid series (promyelocytes and neutrophile myelocytes), naphtol-AS-D-chloracetate esterase shows a more intensive reaction in healthy cattle, as compared with cattle suffering from leucosis.

Animals↗
PubMed1996

Esterase coupled with the H2O2/horseradish peroxidase system triggers chemiluminescence from 2-methyl-1-propenylbenzoate: a potential analytical tool for esterase analysis.

The hydrolysis of 2-methyl-1-propenylbenzoate catalyzed by esterase produces 2-methyl-1-propenol, which can be subsequently oxidized by the H2O2/horseradish peroxidase (HRP) system to yield electronically excited triplet acetone. The level of luminescence elicited by this species is proportional to total esterase used, making it possible to determine as little as 2 pmol of esterase. Yet, its intensity can be enhanced several orders of magnitude by fluorescent acceptors like sodium 9,10-dibromoanthracene-2-sulfonate. The system works as a chemiluminescent reaction triggered by esterase and can be used to elaborate analytical assays to determine its activity. This chemiluminescence is also promoted by HRP conjugates instead of free HRP and, hence, this simple reaction system can also be used to develop sensitive chemiluminescent immunoassays based upon peroxidase activity.

Aldehydes↗
PubMed1975

[Esterase XX. Disc-electrophoretic investigations on the polymorphism of the esterases of the house mouse (author's transl)].

For the further clarification of the polymorphism of mouse-esterase and its hormonal control, which in part have not yet been fully comprehended, disc-electrophoretic analyses of eight organs were made, using a strain with the Tfm-mutation. In addition, quantitative assays of esterase activity as well as histochemical studies were performed. The individual organs are characterized by a specific banding pattern of esterase, which is essentially conditioned by the diverse activity of a limited number of bands. Partly these may be regarded as primary gene products, partly they seem to be secondary modifications. The few incidences of band-linkage justify the expectations, that further gene loci will be discovered. In four organs of Tfm-mutants a lower esterase activity was found than in the controls, which was especially distinct in the kidney. The behaviour of the testosterone-dependent bands in the kidneys of Tfm-mutants seems to indicate two different mechanisms of the effect of testosterone on these bands.

Animals↗
PubMed1975

Macrophage esterase: identification, purification and properties of a chymotrypsin-like esterase from lung that hydrolyses and transfers nonpolar amino acid esters.

A chymotrypsin-like esterase was purified from beef lung. This lysosomal enzyme, not previously characterized, seemed to be composed of two or more forms with molecular weights of about 52 000. It hydrolysed N-benzoyl-DL-phenylalanine beta-naphthol ester at acid and neutral pH; it polymerized L-phenylalanine methyl ester(Phe-OMe) at neutral pH; and it transferred the Phe-residue from Phe-OMe to hydroxylamine at neutral pH. Phenylmethanesulfonyl fluoride, an inhibitor of hydrolytic enzymes with serine in their catalytic site, inhibited this enzyme, but pepstatin, the cathepsin D (EC 3.4.4.23) inhibitor, did not. Sulfhydryl reagents were not required for activity. Macrophages, especially pulmonary alveolar macrophages, were a rich source of this esterase, so it is likely that the enzyme purified from lung came from its macrophages. The esterase hydrolysed and transferred monoamino acid esters, especially those of the aromatic type. Cathepsin C, the dipeptidyl peptide hydrolase (EC 3.4.14.1), acted only on dipeptide esters and amides. Pancreatic chymotrypsin acted on both monoamino acid and dipeptide esters. The chymotrypsin-like esterase did not hydrolyse hemoglobin, casein, or plasma albumin. Thus its proteolytic activity, if present, must be limited to specific substrates, as yet unknown.

Amino Acids↗
PubMed1986

Regulation by serine esterase of histamine release from human leukocytes--I. Direct release of histamine by the serine esterase inhibitors diisopropyl fluorophosphate (DFP) and soman (GD).

The serine esterase inhibitor diisopropyl fluorophosphate (DFP) had been reported previously to inhibit IgE-dependent histamine release. Recently, it has been demonstrated that lower concentrations of DFP enhance IgE-dependent histamine release and inhibit desensitization. This manuscript describes the abilities of several esterase inhibitors to cause release of histamine from human leukocytes (basophils), by a process that is IgE-independent. This esterase inhibitor-induced histamine release appears to be by a non-cytotoxic mechanism that requires calcium and is temperature dependent. These histamine release processes occurred over a longer period of time than IgE-dependent release. Direct release of histamine by these small molecular weight inhibitors and inhibition of desensitization both suggest that one or more serine esterases are involved in the regulation of histamine release from human basophils.

Edetic Acid↗
PubMed1986

The distribution of N-acetyl-beta-glucosaminidase, beta-glucuronidase, acid alpha-naphthyl acetate esterase and alpha-naphthyl acetate esterase in subpopulations of thymocytes, bone marrow cells and other lymphoid organs in mice.

Thymocytes, bone marrow lymphocytes, as well as lymphocytes from spleen, lymphoid nodes and peripheral blood were obtained from BALB/c mice. Subpopulations of BALB/c bone marrow T-lymphocyte precursors and immature (small) and mature (large) thymocytes, as established by the percentage of terminal deoxynucleotidyl transferase (TdT) and peanut agglutinin (PNA) positive cells, were obtained by centrifugation on discontinuous density gradients. The activities of N-acetyl-beta-glucosaminidase (NAG), beta-glucuronidase (BG), acid alpha-naphthyl acetate esterase (ANAE) and alpha-naphthyl acetate esterase (NAE) were determined by enzymatic assays of cell extracts of the diverse T-lymphocyte subpopulations, in order to follow their evolution with the maturation of the T-lymphocytes in the thymus. These activities were compared with that determined in lymphocytes from spleen, lymphoid nodes and peripheral blood. The glucidases BG and NAG and the esterases ANAE and NAE present a high decrease in their activities from bone marrow T-lymphocyte progenitors to immature thymocytes. BG, NAG and ANAE activities undergo an about 3-fold increase with the evolution of the thymocytes from small to large cells. Whereas the level of the NAE activity decreases (2-fold) with that evolution of the thymocytes. Lymphocytes from spleen and lymphoid nodes exhibit activities of the glucidases and, specially, the esterases marked by higher than those of thymocyte populations. Peripheral blood lymphocytes also present NAG, ANAE and NAE activities higher than in thymocytes, but their BG activity is lower.

Animals↗
PubMed1976

Arginine esterase in cerebrospinal fluid and pro-arginine esterase in plasma from patients with migraine.

Estimates of prekallikrein levels in plasma specimens from patients with migraine and from healthy individuals were obtained by determining the benzoyl-arginine ethyl ester (BAEe) esterase activities developed on activation with kaolin, as suggested by Costerase level- 'n the patients and in the control material, and kinetic data provided no evidence of a difference in inhibitor levels. Only very low BAEe esterase activity was registered in samples of cerebrospinal fluid obtained from the patients and no significant difference between attacks and free intervals was detected. When citrated EDTA-treated plasma was activated with acetone-incubated normal plasma containing prekallikrein activator (factor XIIf), no significant difference in BAEe esterase activity was noticed between plasma from the patients and that from the control persons. When, however, citrated plasma without EDTA was used, a significantly higher peak level of esterase activity was registered in the patient plasma. This observation might suggest the presence of a factor positioned between active factor XII and prekallikrein, and present in higher amounts in plasma from patients with migraine than in healthy individuals.

Adolescent↗
PubMed1995

Stereoselective production of (+)-trans-chrysanthemic acid by a microbial esterase: cloning, nucleotide sequence, and overexpression of the esterase gene of Arthrobacter globiformis in Escherichia coli.

The gene coding for a novel esterase which stereoselectively hydrolyzes the (+)-trans (1R,3R) stereoisomer of ethyl chrysanthemate was cloned from Arthrobacter globiformis SC-6-98-28 and overexpressed in Escherichia coli. The cellular content of the active enzyme reached 33% of the total soluble protein in the recombinant E. coli JM105 cells and 5.6 g/liter of culture by high-density cell cultivation. The hydrolytic activity of the recombinant E. coli cells for ethyl chrysanthemate reached 605 mumol of chrysanthemic acid per min per g of dry cells, which is approximately 2,500-fold higher than that of A. globiformis cells. The stereoselective hydrolysis by the recombinant E. coli cells was efficient at substrate concentrations of up to 40% by removing the produced chrysanthemic acid by ultrafiltration. The (+)-trans-chrysanthemic acid produced had 100% optical purity. The amino acid sequence of the esterase was found to be similar to that of several class C beta-lactamases, D,D-carboxypeptidase, D-aminopeptidase, 6-aminohexanoate-dimer hydrolase, and Pseudomonas esterase. The sequence comparison also suggested that the Ser-X-X-Lys motif in the esterase was at the active site of the enzyme.

Amino Acid Sequence↗