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At least 19 recordsLinked to original sources
PubMed1982

Kidney esterases of Mus musculus: further polymorphism of esterase-6, esterase-9, and a new esterase, esterase-20.

The comparison of results obtained by different separation and staining techniques permits the definition of esterase-6 in comparison with esterase-9 and a new esterase, esterase-20. Alleles of Es-6 affect the product's ability to aggregate. Esterase-20 may be an aggregated product of Es-9. The close linkage of Es-6 and Es-9 is confirmed. Homology of esterase-6 with esterases from other mammalian species is also suggested.

Alleles↗
PubMed2001

Esterase isozyme polymorphism, specific and nonspecific esterase, syngenic lines development and natural occurrence of a thermostable esterase in the tropical silkworm Bombyx mori L.

Esterase isozyme polymorphism was documented for digestive juice and haemolymph of the tropical multivoltine silkworm, Bombyx mori L., breed CB5 (GP) and its syngenic lines (CB5Lm(e)-1, CB5Lm-2 and CB5Lm-5) using alpha- and beta-naphthylacetate separately as nonspecific substrates (Ogita, Z., Kasai, T., 1965. Genetico-biochemical analysis of specific esterases in Musca domestica. Jpn. J. Genet. 40, 173-184). Polymorphism existed in the isozyme pattern of alpha-esterase with two or three bands in digestive juice and three to five bands in haemolymph. No polymorphism was observed in beta-esterase isozyme pattern having four bands in digestive juice and two bands in haemolymph. During the course of esterase isozyme studies, the presence of some specific alpha-esterase bands (Est-1, 4 and 5) in haemolymph and beta-esterase bands (Est-1, 2 and 3) in digestive juice were observed. But both alpha- and beta-esterase bands Est-3 and 4 in digestive juice and Est-2 and 3 in haemolymph were found to be nonspecific. Nonspecific beta-esterase band (Est-3) in haemolymph of CB5 (GP) and its syngenic lines withstood a temperature up to 80+/-1 degrees C for 10 min. No thermostable band was observed in the isozyme zymogram of alpha-esterase in digestive juice and haemolymph or beta-esterase in digestive juice. Overall, this study discusses the presence of esterase heterogeneity in the CB5 (GP) genepool, syngenic lines development, occurrence of specific alpha- and beta-esterase bands in digestive juice and haemolymph and thermostable beta-esterase band Est-3 in haemolymph in tropical silkworm Bombyx mori L.

Animals↗
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↗
PubMed1977

Esterases of laboratory-reared and field-collected cotton boll weevils, Anthonomus grandis Boh.: polymorphism of adult esterases and formal genetics of esterase II.

The esterases of the cotton boll weevil were separated by polyacrylamide gel electrophoresis into four major regions. These were named Est I-IV in order of migration from anode to origin. Polymorphism was observed in all regions. The Est II region was shown to consist of no more than two bands (fast and slow). The inheritance of the fast and slow bands of Est II was demonstrated to be controlled by codominant autosomal alleles. Analysis of the gene frequency of the Est II region showed that one field population was consistent with the Hardy-Weinberg law (P = 0.995), while a second field population was not at equilibrium (P less than 0.001).

Animals↗
PubMed1969

Esterases of the polymorphonuclear leukocyte capable of hydrolyzing acetyl DL-phenyl-alanine beta-naphthyl ester. Relationship to the activatable esterase of chemotaxis.

Previous published work has led to the hypothesis that the activatable esterase of chemotaxis is a serine esterase of the rabbit polymorphonuclear leukocyte existing in an inert, phosphonate insusceptible form, which after activation is capable of hydrolyzing aromatic amino acid esters and being inhibited by phosphonates. In the present study, directed to the testing of this hypothesis, we have shown that rabbit peritoneal polymorphonuclear leukocytes contain three esterases capable of hydrolyzing the aromatic amino acid ester, acetyl DL-phenylalanine beta-naphthyl ester. Two of these esterases, esterase 1 and esterase 2, are inhibited by various p-nitrophenyl ethyl phosphonate esters. The inhibition of each esterase is irreversible and progressive with time. When the logarithm of the esterase activity remaining after cell and inhibitor have been in contact for a constant time is plotted against the concentration of inhibitor, a straight line results. These results support the conclusion that both esterases are serine esterases. The third esterase, esterase 3, differs from the other two by its inability to be inactivated by any of the phosphonates no matter how high the concentration of phosphonate or prolonged the period of incubation of cell with phosphonate. The activity of esterase 1 is at least 10,000 times more easily inhibited by phosphonates than is that of esterase 2; incubating rabbit polymorphonuclear leukocytes for 15 min at 27 degrees C with 10(-9)-10(-8)M concentrations of various phosphonates inactivates esterase 1, but it required 10(-6)-10(-4)M concentrations of the same phosphonates to inhibit esterase 2. The inhibition profiles of esterase 1 are distinctly different from those of esterase 2 when the two esterases are tested with the phenylalkylphosphonates, chloroalkylphosphonates, and alkylphosphonates. The inhibition profile of esterase 1 is essentially the same as that of the activatable esterase of chemotaxis obtained previously when the same three homologous series of phosphonates were tested for their ability to protect against deactivation by the chemotactic factor or give chemotactic-dependent inhibition. It is tentatively concluded that esterase 1 of the rabbit peritoneal neutrophil is the activated form of the activatable esterase of chemotaxis.

Animals↗
PubMed1981

Evidence for an androgen-dependent urinary arginine esterase in the rat: separation from other urinary arginine esterases including kallikrein.

DEAE-Sephadex chromatography of male rat urine resolved three peaks of arginine esterase activity using the synthetic substrate alpha-N-p-tosyl-L-arginine methyl ester . HCl (Tos-Arg-O-Me). Esterase activity in peak 1 (esterase A1 fraction) was present in sexually mature males, but it was not found in mature females, castrated mature males, or sexually immature males. Urinary esterase A1 activity could be restored in castrated mature males by the administration of testosterone, and it is, therefore, androgen dependent. Esterase A1 activity was undetectable and could not be induced in females by daily doses of testosterone (up to 20 mg/day). The second urinary esterase peak (esterase A2 fraction) and the third peak (urinary kallikrein) were found in both male and female rats. Molecular sieve chromatography of esterase fractions A1, A2, and kallikrein, as determined by Sephacryl S-200 chromatography, gave single peaks of activity. Molecular weights were estimated to be 28,500, 42,000, and 41,500, respectively. Kinin-generating activities of esterases A1, A2, and kallikrein were also determined using dog plasma substrate. Esterase A1 fraction had no kinin-generating activity, while esterase A2 fraction demonstrated significant activity but was 12 times less active than kallikrein per Tos-Arg-O-Me esterase unit. Esterase A2 fraction could not induce direct contraction of the rat uterus, and A2 did not cause a transient decrease in rat blood pressure when injected iv, both of which are criteria for kallikrein activity. It is concluded that the androgen-dependent Tos-Arg-O-Me esterase has properties quite different from both esterase A2 and kallikrein. Esterase A2 appears to be similar to the esterase A described in female rat urine by Nustad and Pierce.

Animals↗
PubMed1997

An Aspergillus niger esterase (ferulic acid esterase III) and a recombinant Pseudomonas fluorescens subsp. cellulosa esterase (Xy1D) release a 5-5' ferulic dehydrodimer (diferulic acid) from barley and wheat cell walls.

Diferulate esters strengthen and cross-link primary plant cell walls and help to defend the plant from invading microbes. Phenolics also limit the degradation of plant cell walls by saprophytic microbes and by anaerobic microorganisms in the rumen. We show that incubation of wheat and barley cell walls with ferulic acid esterase from Aspergillus niger (FAE-III) or Pseudomonas fluorescens (Xy1D), together with either xylanase I from Aspergillus niger, Trichoderma viride xylanase, or xylanase from Pseudomonas fluorescens (XylA), leads to release of the ferulate dimer 5-5' diFA [(E,E)-4,4'-dihydroxy-5,5'-dimethoxy-3,3'-bicinnamic acid]. Direct saponification of the cell walls without enzyme treatment released the following five identifiable ferulate dimers (in order of abundance): (Z)-beta-(4-[(E)-2-carboxyvinyl]-2-methoxyphenoxy)-4-hydroxy-3-methoxycinnamic acid, trans-5-[(E)-2-carboxyvinyl]-2-(4-hydroxy-3-methoxy-phenyl) -7-methoxy-2, 3-dihydrobenzofuran-3-carboxylic acid, 5-5' diFA, (E,E)-4, 4'-dihydroxy-3, 5'-dimethoxy-beta, 3'-bicinnamic acid, and trans-7-hydroxy-1-(4-hydroxy-3-methoxyphenyl) -6-methoxy-1, 2-dihydronaphthalene-2, 3-dicarboxylic acid. Incubation of the wheat or barley cell walls with xylanase, followed by saponification of the solubilized fraction, yielded 5-5'diFA and, in some cases, certain of the above dimers, depending on the xylanase used. These experiments demonstrate that FAE-III and XYLD specifically release only esters of 5-5'diFA from either xylanase-treated or insoluble fractions of cell walls, even though other esterified dimers were solubilized by preincubation with xylanase. It is also concluded that the esterified dimer content of the xylanase-solubilized fraction depends on the source of the xylanase.

Aspergillus niger↗
PubMed1984

Hormonally sensitive esterase activity in the mouse uterus results from uptake of plasma esterase.

Mouse uterine homogenates contain an estrogen-sensitive serine esterase (hydrolase II). In immature animals, hydrolase II levels increase rapidly after the administration of estradiol. However, stimulation of de novo synthesis in the uterus has not been demonstrated. In this communication we show that hydrolase II activity in the uterus results from uptake of an esterase from the blood. We describe the purification of this protein from mouse plasma and discuss some of its properties. It appears to be similar if not identical to a sexually dimorphic plasma esterase called albumin esterase or esterase 1 by others. Consistent with this, hydrolysis of estradiol valerate and beta-alanine nitrophenyl ester by either uterine homogenates or purified esterase 1 was blocked by heating or by incubation with diisopropyl flurophosphate or antibody to esterase 1. Levels of the plasma esterase (esterase 1) were 50% higher in adult female mice than in adult males. Levels in juvenile males were in between those in the adult males and females. No significant changes in esterase 1 plasma levels in any group were detected after 4 days of treatment with either testosterone or estradiol. Like the uptake of other plasma proteins, estrogen-stimulated uterine uptake of the plasma esterase was inhibited by prednisolone, but not by puromycin. Using immunoprecipitation of [35S]methionine-labeled esterase 1 prepared in a cell-free translation system, mRNA specific for esterase 1 was found in mouse liver, but not in mouse uterus. Although the natural substrate for esterase 1 (or hydrolase II) is not known, both the purified enzyme and uterine homogenates were able to hydrolyze the valerate ester of estradiol, but not the stearate ester. However, estradiol esters are not necessarily the natural substrates of esterase 1, as only the long chain fatty esters of estradiol are reported to occur in vivo.

Aging↗
PubMed1987

Genetics of esterases in Drosophila. IX. Characterization of the JH-esterase in D. virilis.

The kinetic characteristics of the main isozymes of Drosophila virilis esterase were studied and Km values of esterase-2, -4, and -6 and p-esterase for alpha- and beta-naphthyl acetate were obtained. Juvenile hormone (JH) was shown to inhibit the p-esterase activity when in competition with beta-naphthyl acetate and the general esterase inhibitor, diisopropylphosphofluoridate (DFP), was shown to inhibit all the components of the D. virilis esterase patterns except p-esterase. While studying the changes of p-esterase activity in D. virilis ontogenesis, the increase in p-esterase activity in the wandering larvae, prepupae, and early pupae was found to correlate with a decrease in JH titer at these stages. The decrease in JH level in a temperature-sensitive lethal mutant larvae of D. virilis at high temperatures was shown to correlate with increased p-esterase activity. These results confirm that p-esterase of D. virilis is JH-esterase.

Animals↗
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↗
PubMed1984

Inhibition of non-specific leukocyte esterase activity. Absence of monocyte esterase activity due to phosphoric and thiophosphoric acid ester intoxication.

In vitro evaluation of the effect of five insecticidal phosphoric and 11 thiophosphoric acid esters on different, non-specific human leukocytes esterases indicated that most of the organic phosphor compounds studied inhibited the activity of neutral alpha-naphthylacetate esterase, alpha-naphthylbutyryl esterase, and naphthol AS acetate esterase, i.e. the monocyte esterases. The extent of inhibition was dose dependent; the inhibiting dose being identical for the various non-specific esterases. Reactivation with Obidoxim was not successful. Monocyte esterase activity in a human survivor of E 605 intoxication was detectable only after serum acetylcholinesterase had returned to normal levels. The organic phosphor compound studied, however, inhibited neither acid alpha-naphthylacetate esterase nor naphthol AS-D chloroacetate esterase activity.

Adolescent↗
PubMed1990

Pancreatic cholesterol esterases. 1. Pancreatic cholesterol esterase induction during maturation.

The activities of pancreatic cholesterol esterase from calf and cow pancreas were examined in detail. A 1300-fold enhancement of enzymatic activity was found after maturation, even though cholesterol esterase activity levels in other organs did not change from the juvenile to the adult species. Radioimmunoassays also showed that the calf pancreas contained at least 100-fold less cholesterol esterase protein. Decreased amounts of protein were not due to enhanced proteolysis, since cytosol from cow pancreas degrades exogenously added cholesterol esterase faster than that from calf pancreas. Rather, enhancement of pancreatic cholesterol esterase activity associated with bovine maturation was the result of specific, increased synthesis of a 72-kDa enzyme. This labile 72-kDa cholesterol esterase species was purified to homogeneity by a two-step process in 75% yield and is the major form of bovine pancreatic cholesterol esterase (99%). A much less abundant 67-kDa species, accounting for less than 1% of total pancreatic cholesterol esterase activity, was also purified to homogeneity in a similar two-step process. These results demonstrate that a specific form of pancreatic cholesterol esterase is induced during maturation, and they bear importantly on understanding juvenile cholesterol metabolism as related to dietary absorption of this sterol.

Aging↗
PubMed1986

Monocyte nonspecific esterase. Enzymologic characterization of a neutral serine esterase associated with myeloid cells.

Monocytes contain a characteristic, prominent set of membrane-bound nonspecific esterases with a slightly acid isoelectric point. These esterases are also detected at modest levels in some granulocyte preparations. They are not apparent in lymphocytes. Among 18 fresh myeloid leukemias and myeloid leukemia cell lines, those of subtypes M4 (myelomonocytic) and M5 (monocytic) were strongly positive; some of subtypes M1-M3 (granulocytic) were moderately positive. The esterases were not detected among 32 fresh lymphoid leukemias and lymphoid leukemia and lymphoblast cell lines. The membrane-bound monocyte esterases, solubilized by treatment of monocyte preparations with nonionic detergent, were resolved by ion-exchange chromatography. The monocyte species account for 80-95% of the total nonspecific esterase activity of monocytes. The resolved enzymes behave as neutral serine carboxyl esterases and are highly sensitive to inhibition by diisopropylfluorophosphate (DFP) and also by sodium fluoride. Similar analysis of a lymphocyte preparation yielded no detectable monocyte esterases, but yielded numerous other forms which were generally resistant to inhibition by DFP and NaF. These nonspecific esterases are also present at background levels in monocytes. The resolution and characterization of the membrane-bound serine esterases from monocytes demonstrates the basis for the well-known cytochemistry of monocytes. The results are also crucial to the development of an immunologic surface marker test for myeloid cells and the study of monocyte membrane physiology.

Adolescent↗
PubMed1989

Identity of a cytosolic neutral cholesterol esterase in rat liver with the bile salt stimulated cholesterol esterase in pancreas.

A neutral cholesterol esterase has been purified to homogeneity from the cytosolic fraction of rat liver. The 105,000 x g supernatant fraction of rat liver was applied to a DEAE-cellulose column to isolate a partially purified fraction of hepatic cholesterol esterase. Immunoblot analysis of the partially purified liver fraction with the anti-porcine pancreatic cholesterol esterase IgG demonstrated a single band with a molecular weight of 67,000. The hepatic protein was then isolated by immunoaffinity chromatography technique using a column constructed with antibodies prepared against the pancreatic cholesterol esterase. Characterization of the hepatic cholesterol esterase revealed that the hepatic enzyme shared antigenic epitopes with the pancreatic cholesterol esterase and was similarly activated by addition of bile salt such as taurocholate. Moreover, amino-terminal sequencing analysis of the hepatic cholesterol esterase showed an identical sequence with the pancreatic enzyme. Taken together, these results showed that the cholesterol esterases in the liver and the pancreas are very similar and possibly identical proteins.

Amino Acid Sequence↗
PubMed1991

Estradiol esters can replace 17 beta-estradiol in the stimulation of DNA and esterase synthesis by MCF-7 cells: a possible role for the estrogen-sensitive MCF-7 cell esterase.

In this communication we extend our earlier observations on estrogen-sensitive carboxyl esterases in MCF-7 human breast cancer cells able to hydrolyze esters of estradiol. Using either estradiol acetate or p-nitrophenyl hexanoate as substrates, esterase activity was found to increase 2-3-fold in MCF-7 cells maintained in the presence of 10(-8) M estradiol. Following sucrose density centrifugation, over 85% of total esterase activity was found in the cytoplasmic fraction. No esterase activity was found in spent media from growing cells. By size exclusion chromatography, estradiol acetate esterase activity exhibited a mol. wt of 45-50 kDa. Attempts to demonstrate incorporation of [3H]estradiol into estradiol fatty acid esters by the above MCF-7 cell line (203P) were unsuccessful, although, such incorporation could be demonstrated in two other MCF-7 cell sublines. Incubation of the 203P cells with 10 nM [3H]estradiol in the presence of 0.5 mM radioinert estradiol acetate resulted in the incorporation of 35 +/- 12% of the label into the estradiol acetate in 10 min. In the absence of radioinert estradiol acetate, no incorporation was observed. When MCF-7 cells were incubated with [3H]estradiol in the presence of a large excess of radioinert estradiol valerate, label was found only in estradiol valerate. Similarly, when the incubation was carried out in the presence of a mixture of radioinert estradiol acetate and valerate, label was incorporated into both esters. We conclude that the apparent formation of radiolabeled estradiol esters by MCF-7 cells incubated under the above conditions, results at least in part, from an esterase-catalyzed exchange reaction. Under conditions where no ester hydrolysis could be detected in the absence of cells, valerate and stearate esters of estradiol were found to be as effective as unesterified estradiol in stimulating esterase synthesis and the incorporation of [3H]thymidine into DNA. These results are consistent with a model in which an intracellular esterase in MCF-7 cells can generate estradiol from an exogenous lipoidal steroid and elicit an estrogen response.

Acetates↗
PubMed1991

BLT-esterase activity following in vitro and in vivo activation of human lymphocytes with interleukin-2. In vivo IL-2 induces BLT-esterase.

BLT-esterase and cytolytic activity by human in vitro and in vivo generated Lymphokine Activated Killer (LAK) cells were measured. Lysates made from peripheral blood lymphocytes (PBL) of both normal donors and cancer patients receiving IL-2 therapy were assayed for BLT-esterase activity in a spectro-photometric assay. Cytotoxicity of PBL was measured in a 51Cr-release assay. Both BLT-esterase activity and cytotoxicity increased when normal-donor PBL were stimulated in vitro with IL-2, with greater activities at higher IL-2 concentrations. The activities also increased over time, peaking at 6 days of in vitro stimulation. Patient PBL had increased BLT-esterase and cytotoxic activities after 4 weeks of in vivo IL-2 treatment. This association of BLT-esterase activity and cytotoxicity with IL-2 activation is consistent with the model that LAK cytotoxicity is mediated by secretion of BLT-esterase associated cytolytic granules. Lymphocytes obtained after in vivo IL-2 treatment and cultured for 3-4 hours in IL-2 show markedly augmented cytotoxic activity but no increase in their BLT-esterase activity. These results indicate that the increased cytotoxicity observed after this brief pulse of in vitro IL-2 following in vivo IL-2 treatment must result from effects of IL-2 other than the production of more esterase-containing cytolytic granules.

Cell Survival↗