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At least 19 recordsLinked to original sources
PubMed1975

Esterase-6 (Es-6) in laboratory mice: hormone-influenced expression and linkage relationship to oligosyndactylism (Os), esterase-1 (Es-1), and esterase-2 (Es-2) in chromosome 8.

Allelic differences at an esterase locus designated Es-6 exist between mouse strain C57 BL/6J and a laboratory stock of M.m. molossinus. Strain C57BL/6J has been assigned the allele Es-6a and M. m. molossinus the alternate allele Es-6b. Kidney expression of the electrophoretic esterase band controlled by the Es-6 locus is sex influenced, with increased activity apparently induced by testosterone. A four-point test cross established the gene order Os-Es-1-Es-6-Es-2 within a 10-cM segment on chromosome 8.

Alleles↗
PubMed1976

Genetics of esterases in Drosophila. IV. Slow-migrating S-esterase in Drosophila of the virilis group.

A slow-migrating beta-esterase (S-esterase) is described which has been detected in Drosophila montana, Drosophila imeretensis, and some stocks of Drosophila virilis when mixtures of alpha- and beta-naphthyl acetate are used as substrates in histochemical reactions after electrophoresis. Sexual dimorphism for S-esterase has been demonstrated. This esterase is contained in male genitalia only, predominantly in the ejaculatory bulb (waxy plug). It appears 3-4 days after emergence of flies. In hybrids between S+ and So species, the activity of the slow esterase is either decreased or inhibited. An autonomous synthesis of the S- esterase in the ejaculatory bulb was established by transplantation of imaginal genital discs into larvae of different Drosophila stocks. Based on analysis of physiochemical and immunochemical properties, S-esterase is suggested to be an independent fraction of esterase, possibly dimeric, which does not cross-react with beta-esterase antiserum.

Animals↗
PubMed1979

Serum esterase genetics: identification and hormone induction of the Es-1b esterase in inbred rats.

A previously unrecognized esterase from the sera of the appropriate strains of the rat Rattus norvegicus was revealed by a discontinuous polyacrylamide gel electrophoretic technique. This esterase migrated in the albumin region, whereas a previously known major albumin esterase controlled by the Es-2 locus migrated in the postalbumin region when the method was used. The new albumin esterase component which separated from the Es-2 esterase was identified as the product of the Es-1b gene. The new albumin esterase was not detectable in the sera of sexually mature males of the appropriate genotype, because the activity level of this esterase was influenced by sex hormones, especially androgen.

Age Factors↗
PubMed1979

Chronologic changes of activities of naphthol AS-D acetate esterase and other nonspecific esterases in the mononuclear phagocytes of tuberculous lesions.

Nonspecific esterases of mononuclear phagocytes (MNs) were studied histochemically in the developing and healing tuberculous lesions produced in rabbit skin by bacille Calmette Guérin (BCG). Nonspecific esterases were assayed with the following substrates: naphthol AS-D acetate (AS-D), naphthol AS-D chloroacetate (AS-D Chl), naphthol AS acetate (AS) and alpha-naphthyl acetate (alpha-N), beta-Galactosidase, a lysosomal enzyme of MNs, was also assayed as a marker of MN activation. The number of MNs hydrolyzing AS-D Chl, AS, and alpha-N increased for 2 to 4 weeks after infection. These chronologic changes were similar to that of beta-galactosidase. In contrast, MNs hydrolyzing AS-D appeared predominantly in the healing lesions five to six weeks after infection. These MNs had the morphologic features of balloon-like cells. They contained few lysosomes and gathered in clumps far from the caseous center. The activity of the AS-D esterase was almost completely inhibited by various trypsin inhibitors, but not by the serine esterase inhibitor of phenylmethylsulfonyl-fluoride. These results suggest that the AS-D esterase is a trypsin-like esterase which participates in the healing of tuberculous lesions.

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↗
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↗
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↗
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↗
PubMed1979

Effect of halogenated benzenes on acetanilide esterase, acetanilide hydroxylase and procaine esterase in rats.

1,2,4-Trichlorobenzene, 1,3,5-trichlorobenzene, hexachlorobenzene, 1,2,4-tribromobenzene, 1,3,5-tribromobenzene and hexabromobenzene were compared for their abilities to induce acetanilide esterase, acentailide hydroxylase and procaine esterase. Except for hexabromobenzene all induced acetanilide esterase whereas the hydroxylation of acetanilide was seen only with the fully halogenated benzenes and with 1,3,5-tribromobenzene. Hepatic procaine esterase activity was increased by the three chlorinated benzenes and 1,2,4-tribromobenzene.

Acetanilides↗
PubMed1978

Esterase XXVII. Purification and characterization of esterase-9A of mouse kidney.

Esterase-9A, which appears electrophoretically as a triplet of the bands III-50, III-40 and III-30, was isolated from the kidneys of male NMRI-mice by isoelectrofocusing and refocusing followed by repeated molecular sieve chromography. The overall purification was approx. 250 fold and each of the three bands was isolated separately. The band of the triplet nearest to the cathode, III-50, changed in vitro into the satellite bands III-40 and III-30 and, further, into the band III-22 not observed before in the homogenate. It is assumed that the band III-50 represents the original gene product. The molecular weight (45 000) of the band III-50 is identical with those of III-40 and III-30, as measured by analytical electrophoresis, whereas the molecular weight obtained by thin-layer chromatography was 51 000. There were no obvious signs that esterase-9 was composed of subunits. The Km constant for 4-nitrophenyl proprionate was identical for each of three bands. The esterase-9A is the first testosterone-dependent isozyme of the mouse carboxylesterase (carboxylicester hydrolase, EC 3.1.1.1) system which has been isolated.

Animals↗
PubMed1978

Esterase 13, a new mouse esterase locus with recessive expression and its genetic location on chromosome 9.

A new esterase locus (Es-13) has been identified in Musculus. Strains AEJ/GnRk, LG/J, SJL/J, and SWR/J carry a recessive allele, Es-13b, for a locus possibly involved in the posttranslational modification of a kidney esterase. All other strains observed carried the dominant Es-13a allele. Es-13 was mapped on Chr 9 by recombinant inbred lines and by conventional backcrossing experiments. Backcross data produced the following gene order and map distances: Lap-1 (31.6 +/- 7.5 cM) Es-13 (2.6 +/- 2.6 cM) Mod-1.

Animals↗
PubMed1977

Esterase XXV. On the induction of Es-9 esterase of mouse kidney by testosterone.

The Es-9 esterase is expressed in the cortical zone of the NMRI mouse kidney only in the presence of testosterone. In disc electrophoresis, three esterase bands, absent in the control, emerge under the influence of exogenous testosterone, accompanied by the appearance of active sites, as shown by marking with [3H] diisopropyl fluorophosphate ([3H]DFP). It is suggested that the testosterone dependent appearance of Es-9 activity is due to true enzyme induction which requires the presence of an intact testosterone receptor.

Animals↗
PubMed1979

A method for the estimation of esterase synthesis and degradation and its application to evaluate the influence of insulin and glucagon.

The irreversible reaction between liver esterases and the active-site-directed inhibitor bis(4-nitrophenyl)phosphate can be used in vivo both for the estimation of the esterase contents and for the measurement of the esterase degradation rates. A method based on this reaction is described which allows the simultaneous estimation of the rate constants of degradation and synthesis of esterases during a period of change in protein concentration. Rat liver was found to contain about 1 mg of organophosphate-binding esterases per g of fresh tissue while the microsomal fraction contains about 30 mg of esterases per g of microsomal protein. Esterase degradation and de novo synthesis were shown to remain in equilibrium for a period of at least five days following the injection of 10 mg bis(4-nitro-[14C]phenyl)phosphate per kg. The decrease of the relative amount of labeled esterases with time was found to follow first-order kinetics yielding an average esterase degrading constant of 0.0165 h-1 which corresponds to a half-life of 42 h. These data were confirmed by an independent experiment using one of the standard procedures for the estimation of degradation rates: [14C]leucine was incorporated and one of the esterases was subsequently isolated by immuno-precipitation. Using isoelectric focussing and dodecyl sulfate electrophoretic methods, the various esterase isoenzymes appeared to have very similar, if not identical turnover rates. This method for the estimation of the turnover characteristics was applied to evaluate hormone effects on liver esterases. The time course of the contents and the turnover of liver esterases was measured under the influence of glucagon treatment in diabetic rats and under the influence of high doses of insulin. The esterase content decreased faster than the average content of microsomal protein under the influence of glucagon. The reverse effect was observed with insulin-treated rats. Both insulin and glucagon apparently reduced the intracellular esterase turnover in rat liver. Kinetic analysis of the results revealed that insulin mainly lowered the esterase degradation rate, though the rate of esterase synthesis might also have been restricted. In the glucagon-treated rats the de novo synthesis of esterases was strongly reduced.

Animals↗
PubMed1979

Species difference and characterization of intestinal esterase on the hydrolizing activity of ester-type drugs.

The ability of the esterase from intestine was studied for hydrolysis of ester-type drugs during absorption. The intestinal esterase is present in the absorption sites in the intestine and hydrolyzes to a large extent during the absorption. In a study of the dietary effect on intestinal esterase, the esterase activity increased in rats fed a high-fat diet, decreased in those fasted or fed a fat-free diet, whereas the esterase activity in the rat treated with phenobarbital showed no marked change. Thus the esterase from intestinal mucosa appears to be characteristically quite different from hepatic esterase. The esterase from human intestine was characterized and compared with esterase from rats, mice, rabbits, guinea pigs and dogs. There was a difference in the substrate specificity of the esterase and there were significant species differences in the electrophoretic behavior of the enzyme among the species tested. These results indicate that intestinal esterase from humans differs characteristically from esterases in experimental animals.

Animals↗
PubMed1975

Esterase zymograms of Proteus and Providencia.

The intracellular esterases of 80 strains of Proteus and Providencia were analysed by the acrylamide-agarose zymogram technique using several synthetic substrates. The esterase bands were classified in five main groups. The alphaA-esterase bands hydrolysed alpha-naphthyl acetate and were resistant or relatively insensitive to di-isofluoropropyl phosphate (DFP). The alphaB-esterase band hydrolysed both alpha-naphthyl acetate and alpha-naphthyl butyrate and were very sensitive to DFP. Both groups of esterase bands were inactivated by heat. The betaA- and betaB-esterase bands hydrolysed beta-naphthyl acetate and were sensitive to DFP; these were distinguishable by the difference in their relative activity towards beta-naphthyl butyrate and in their relative stability to heat. The alpha-beta-esterase bands hydrolysed alpha- and beta-naphthyl acetates and alpha- and beta-naphthyl butyrates; they were inactivated by heat and were sensitive to DFP. The distribution of these esterase bands among the strains of Proteus and Providencia and their electrophoretic patterns established esterase profile types which correlate with the classification based on traditional bacteriological tests. The degree of inter-strain similarity in esterase pattern varied highly among species. The homogeneity of Proteus mirabilis and especially of Providencia stuartii contrasted with the heterogeneity of other species. This disparity suggests that the bacteria of the tribe Proteae have not the same degree of intra-specific differentiation in physico-chemical properties of esterases.

Butyrates↗